Gif timing question

[beetle_breath]

Hi all!

I'm hoping someone could give me some tips on how to make animated gifs for Tumblr. I understand the basics but timing is getting me down.

I know there's a way to save multiple gifs in one canvas so the first bit finishes before the second, but the file size ends up being way too large or there's too much loss of quality for my liking.

Is there a good way to manually time separate gifs to align properly? I'm using Photoshop CS3.

[crappy example of what I mean]
2 separate images:





Versus one canvas:



Thanks!!