how do i overclock my amd athlon 64 3200+

Well, first, you have to understand what overclocking is and what the dangers are. Yeah yeah, you know it will speed a component up, but, I mean really understand how it works and what it actually does to bus(es)/components involved on an electrical level and everything else in between. Before you say you do, no, you don't because you wouldn't be posting here otherwise.

I suggest you find a decent guide (there are hundreds around). Here are a few links for you:

http://www.anandtech.com/showdoc.aspx?i=157
http://www.compunamics.com/overclocking.htm