How to land a front flip off a diving board?

Whether you have a running or standing start, begin the action with your arms above your head, Push down and back into the diving board with your feet, and allow it to propel you into to air (if it is a springboard that is) bend your knees and throw your arms forward (a similar action to throwing a soccer ball over your head.) Do not drop your head, imagine you are trying to jump over an imaginary bar or fence, (you need height as well as rotation to complete the summersault). Flip your hips up behind you and tuck in your knees, grab your shins, you are now in a tuck position. You should be able to feel that you are upside down and (if you keep your eyes open) you will see the water pass over your head. Wait until you are almost upright again then kick both feet out towards the water. Kicking out of the tuck shape stops your rotation and allows you the control your entry. If you do not make it round, try throwing harder and jumping higher. A running take off will give you more momentum. If you find your self spinning too fast and going over onto your stomach, try either coming out of the summersault earlier or jumping higher and not throwing as hard on the take off. When you get good at a single summersault, try a 1 1/2 (this is where you continue rotating into a head first entry)

The most important part is making sure you tuck your knees. When you jump off the board, bringing your knees in to your chest and then back out again before you land will make sure you spin all the way around. The tucking motion makes your body flip over while you're in the air.