Simple enough it is, no? You form the handseal and focus your chakra to create a perfect clone of yourself, but sadly, he can be easily dispersed by a forceful hit. You can also create more than one (up to 4) clone doing this jutsu, and I'm not sure if you can only make 4 clones per battle, but meh. Try it out first making only one clone, and then try two, and then three, and then finally four simultaneously.