Well,basically you must be ready to do stuff.
Flexybility and speed is the most important ones,you will do most of tricks using legs and arms.
legs to jump and arms to make a body rotation.
Big jumps are useful,but dangerous at same time: if you get too high,you probably wont land on your feets,and with a heavy impact of you legs you probably will lose you balance and fall(pain on legs)(unless you have some strong bones,common strong is enought to avoid the pain and make a good land)
So,basically the most important is flexybility and agility.