Practice somersaults away from the wall first. Exhale through your nose forcefully as you rotate.
Don't slow down before you flip. Your momentum will make the turn easier.
Don't flail your arms everywhere after you're over. This is a major problem for almost all new flippers because the correct arm position is counter-intuitive. When both your arms are at your side and you have not yet swung your legs over, your arms are already in their correct position facing the direction you want to go. You need only turn your hands from palms facing up to palms facing the bottom of the pool.