These are direct copies from part of my enormous guidelines-for-character-creation-in-upcoming-City-campaign document, so they are far from the most polished mini-essays I've ever written. That being said, I wrote them to portray my perspective on building characters for my City players as most of them are somewhat new to the game, and I figured it couldn't hurt to post those notes here.
Building and playing highly vibrant and realistic characters:
I gave a (honestly, better) verbal version of this speech to Sean once in the car, and it seemed to help him a bit, so I figured I’d give a sparknotes version here, seeing as you can read or not read at your choice. This is not intended to patronize, but rather to give something of my perspective on things that I feel really enhance both the believability of your character and your enjoyment in playing them.
First off, there are really three parts to building your character: backstory, personality (currently) and mechanical build. Obviously, they should all reflect each other, but as the build part is rather obvious and can be manipulated via reflavoring (which is super easy in 4.0), I’m not going to bother talking about that.
Instead, of the other two, I’ll mention the easier one first: backstory. We all know what it is. It’s where you came from, what you’ve done, what you know, what you want, and how you got here - to whatever point in your life you’re at during the start of campaign. Some people have more focus on their childhood, others on more recent life events - the choice is yours. The most important and most overlooked part of backstory, however, is how it impacts your character’s worldview. Have you learned that interacting with other people gets you what you want, or do your experiences show that you work best alone? Did you grow up without a family - causing you to view other people as surrogate family members rather than simply friends? Have you been rejected so many times that you are standoffish, until you find something real and cling to it?
Keep in mind that when writing your backstory, you aren’t just writing a series of events that happened in your past; you’re writing the lens through which you view the world, the lens that defines your fears, your morals, your loves, and your hates. You could be a noble who ran away from his oppressive family life and joined the army, and today you spit and curse and forget to wash out bloodstains just as frequently as any of the men under your command.
But it’s important to consider more than just the fact that you secretly know proper table manners and court etiquette. How did you get to where you are today? Your handling of the transition phase likely defined who you became. If your home life was miserable enough to leave, you might not have a solid enough understanding of what a real family should be, to the point that maybe you sometimes have trouble empathizing with your troops’ desire to see their siblings, or understand why Lee took a sword to the stomach for his oft-complaining little brother Don.
What did your shift from wealth to soldiers’ rations teach you? Likely you complained frequently but quietly and often messed up simple chores, much to your humiliation. After such displays, likely you had to fight twice as hard as other commanders to gain the respect of your soldiers, and now that you have learned a more humble life through sheer determination, you might be desperate to avoid going back how you used to be (because you know it is possible for you to backslide - the easy life was really very tempting, and it would be so simple to get lost in the slide of empty days) and bowing to the “prissy” nobles who you feel are too weak to learn how to wash laundry and cook meals - because you know they can do it; you did, after all. That viewpoint might have left you with such a disdain for manners and propriety that you may eschew them largely or entirely, even when doing so may carry dire consequences. Considering small, day-to-day events just before, during, and after life-altering events and decisions can make you consider small points like these, and the answers you find can go a long way in fleshing out your character. When considering any action during campaign, think not only of what your character would do, but why they would do it. The “why” tells you how you feel about the situation, and is more useful for understanding how strongly you should react to the matter at hand - and is, though it will likely not be verbally explained to the other players or characters, the more important of these two factors for portraying a realistic character that you (the player) can connect with and understand.
Similarly, when portraying your present-day character, take into account not only the traits which came from your backstory, but also consider possible growth directions for you character. What are your flaws? Are you too concerned with money, and hope for your character to learn more about the value of intangible things? Are you on a redemption quest for something not entirely your fault, and want your character to learn to forgive themselves and properly allocate blame? Do you boast too much and want your character to eat a piece of humble pie to become a person who can gain true confidence? All of these are important flaws and directions to point out and share with the DM prior to campaign. The DM, of course, does not want to unintentionally push your character in a direction the exact opposite to the sort of character you want to play, and while unexpected character development always occurs, DM knowledge can prevent “unexpected” from being “undesired.”
Likewise, do not be afraid to fully portray these flaws during RP. If a fear of pain is a serious problem for your character, they could be just brave enough (or desperate, or bribed) to follow the party, such that they are not left out of sessions - but they might hide in the back of the marching order, and always advise an overly-cautious solution to problems. Similarly, building in minor phobias or quirks that can be overcome with a lot of bribes or talking with PCs can add depth to your character, as can other small issues such as a nervousness around dogs, an unhealthy and reckless obsession with new varieties of tea, or a tendency for your spells to set off small, unnecessary sparkles (which might be attention-getting, but reflect a character’s somewhat twitchy nature). You may need to occasionally come up with new in-character reasons to keep sidelining these personal issues to stay with the party, but that’s okay - you may often find that doing so is easier than you think.
Many such flaws are designed to be overcome in time, but others could represent permanent parts of your character. While these may seem - and in fact are - detrimental, they will significantly enhance your playing experience. You may be initially hesitant about putting your character in danger (as the character themselves would likely be), but so long as you do so in a situation where they have a chance of escape or success, it can be rather thrilling and make your character more three-dimensional. Everyone takes reckless, desperate, ill-considered, or inadvisable courses of action from time to time, albeit frequently with some sort of failsafe or backup.
Similarly, though PC conflict is best avoided, do not be afraid to have your character occasionally oppose a course of action presented by the rest of the party, or confront a party member for an act your character finds particularly reprehensible. So long as you are not unreasonable about doing so and have (and present) a legitimate in-character reason for your opposition (be it on a moral standpoint, it seeming unwise to you, against your religion, etc.), and are willing to find in-character reasons for your character to either eventually agree to the course of action if an alternative is not found, or be willing for your character to take a side role and not directly participate in the main action they disagree with, this is fine.
Similarly, you may sometimes need to simply agree to disagree, or come to the conclusion that a certain pair of characters are simply too different to interact smoothly (though they should at least manage a working relationship, even if interpersonal feelings are a bit strained - “You are more useful to me alive” works wonders here as a way of in-character explanation) at this stage of their development. So long as it does not come to PvP (and it really probably shouldn’t, unless your relationships and/or party dynamic are abysmal - generally no one wants to fight their allies and are willing to try to compromise), such conflict can flesh out your character, and may lead to character development and party dynamic shifts for both you and the other PCs.
And now for a mini-essay on tips for creating backstory NPCs that can involve your character in the story and enhance your involvement:
As a note to those who are not as experienced in making characters - a good backstory that can be integrated into the plot entails not only the usual formative events of your character and their place in the world, but also NPCs who are relevant to the party’s mission or offer potential conflict for the campaign. A father who went missing five years ago, a former partner who went MIA, a rival who framed you and got you kicked out of the district where you grew up (and, obviously, of whom you no longer have track and whose reasons you weren’t entirely clear on), a little brother who was kidnapped by (you think) the Alliance and whom you have forever after kept an ear to the ground for in your spare time, a rogue psion who once possessed you and made you kill a friend though you were eventually acquitted for the crime, or a close childhood friend who unexpectedly betrayed you in some significant way are all good examples of background NPCs who could become relevant to the plot and reappear during campaign as plot-relevant characters.
All of these examples represent an NPC who a) your character will still care about during the time of campaign, and b) who have enough doubt as to their fate, reasons, and/or whereabouts (this last bit is especially important) that while your character may or may not have given up on them, they can be introduced into the story in a vast variety of ways, which are so numerous that you - as the player - cannot predict, which will make the NPC interesting to you and involve your character in particular in the story.
More well-defined characters, such as a mother currently in the city guard, an old schoolmate who now runs a ritual casting shop, or a father who works as a very straight-laced alchemical researcher in Council HQ, are good for fleshing out your character’s history, but have extremely narrow roles. They are so specified that they cannot have more than a once- or twice-plot-relevance without changing the people that you and the DM would have agreed they were pre-campaign, or using a very cliché GASP!he was lying to me all along. These characters are good too, and certainly have a place in your backstory (not that you necessarily need, or should even have, more than one or two or possibly even three major/named NPCs in your backstory. Any more than that is too much to keep track of or flesh out.)
I am very fond of character-specific side plots, and like having one for each PC, so if you want to involve your character in the story using this method, I encourage you to do so. Mostly I wrote all this out so that you can better understand a good way to make your character’s backstory relevant to his or her present in a meaningful way, since it is not always clear exactly how to do so - especially with backstory NPCs, where you must walk a fine line between too much information and not enough.
There are some other ways to make your character’s history relevant to campaign, of course (their relationship - good or bad - to a guild or group with a goal, a hunt for blue dragons after recurring prophetic dreams involving them, or their hunt for a specific artifact that their father spent his life searching for), but recall that your character is a person, and that no matter where they go, the one thing a person will always carry with them is their connections to other people, be it in the form of a memento, a scar, a burning hatred, or a distant longing.
Note, though, that these are only suggestions. While a direct link between a well-crafted backstory and the current campaign can greatly enhance your playing experience, you do not necessarily have to incorporate your history. You can simply be a person going through life without too many more-than-usual complications. How you choose to play is completely up to you - I am merely offering some tips if you want to make NPCs part of your character’s story. Don’t feel pressured by this mini-essay.
Also, as Adam made me consider, if you do want to make a potentially plot-relevant backstory NPC, I actively do not want you to give me any suggestions for incorporating them. Doing so could lead me to cater to/follow such suggestions. While that’s not inherently bad, it really takes away the surprise and emotional value if I bring them in in a way you were anticipating - which in my opinion is sort of the opposite of the point of giving that character an ambiguous exit from your backstory, anyway. If you build an NPC to suit this role you may mention that you “hope they might reappear” if you wish, but please no further. I prefer surprises, myself. ;)