Step one: Spend two days tearing down old, broken, partial fence. Dig very deep holes all around the concrete bases of the posts and pull them out. Use chains when necessary for leverage. Spend the following week feeling like a jackhammer has been dancing around on your arms...
BEFORE:
AFTER:
Step Two: have the utility people come out and mark where all the power & gas lines are.
Step Three: Spend four days digging thirty five new holes... mixing up thirty five 60-lb bags of concrete... and setting thirty five posts in the holes allllll the way around the yard. Drink a lot of water. Occasionally stop to play with dogs and chat with the neighbors.
Step Four: Adding rails, pickets and stain; to be continued. :P