This is a pretty basic explanation of what you need to understand before taking apart your carb to start the jetting process. My write-up, posted as Jetting: Part 1, will get you pretty close. However, it is going to require some personal trial and error on your part to get it just right.
This is nothing too complicated. With a little bit of mechanical ability and some gusto, you'll be fine.
http://www.iwt.com.au/mikunicarb.htm