Now comes the fun part. If you are using an electric buffer of some sort, all you need to do is relax and let the buffer do the work for you. The condition of your paint will tell you how much buffing you need to do. If your paint has zero shine, you'll need to spend a little time on the buffing step. The longer you let the machine polish the more shine you'll get. Don't let the buffer sit in one spot ever! Move it in circles, lines, whatever you need to do to keep it moving and cover the ground you need to cover. You can actually "burn" your paint finish with overzealous spot buffing.
If you're waxing by hand using a hand applicator or a clean, soft rag, you'll need to polish your car in a circular motion, again being sure to keep moving across the body. You can't really burn your paint waxing by hand, so if you are worried or inexperienced it might be worth it to skip the electric buffers altogether.