Read the manual for the Alesis 3630.

http://www.alesis.com/index.php?id=56,30,0,0,1,0

It is for a different unit, but they have all the same controls. The appendix has a complete explanation of the principles behind compression, which I do not feel up to typing out.

As far as presets, anyone will tell you that whatever works, works. But if you google for like 2 minutes you will find all kinds of sites to give loosely "standardized" settings. This is never as good as experimentation with a grasp on the operating principles, though.
Just in case you are feeling lazy, though:

http://www.electronicmusic.com/features/siu/studiohelp/about/compsettings.html

Word?

Word. Thank you very much. The reason I didn't google is because I had only a few minutes and I trusted you guys here to give me straight, real answers.

Start Low and Slow.