Words can't describe how simple freestyle is. Basically its backstroke on your belly. Or backstroke is free on your back. Like the other strokes, breathing is a big feature. To be successful you must control your breathing. When you do breathe, pull your head up just enough to get air and make it quick, breathing can add more time. You must also look at the bottom of the pool to avoid resistance. Below are some diagrams showing how to do so.