Pace Yourself
It's easy to get in over your head when you are just starting out. To keep yourself from burning out before you even have anything to show for your effort, join about 10-15 sites at first (check out the
Top 10 for a good starting point), give those a week, and then join 5 more if you can still fit them in your schedule. Continue until you reach a comfortable balance between time spent doing surveys and everything else.