More than likely u wont break anything on ur body unless u do sumthing REALLY DUMB. Which of course u are probably a intelligent person. Ok, a simple basic suicide practice would be going to a hand stand, flipping over, and releasing ur hands. When ur about to hit the ground, make sure ur feet HIT FIRST. that way ur fall is on ur feet, NOT UR BACK. If u land on ur back first, its REALLY gonna hurt, practice the handstand flip for a bit.
When ur rdy for a regular suicide, jump up and flip. On the way down. time ur placement of ur feet and ur back. If ur feet and back are timed correctly, u should land pain-free.
