The best way to learn to free run is to learn the basic such as standing long jump. this will help build up the quads. u also need to keep a constant weight and drink alot of water. it'd suck if u were jumping a big gap between roofs and u just feint of dehydration. anyways, the constant weight gives u big air. if u'r too heavy, u'r least likely to be able to do awsome jumps and flips. if u work on your standing long jump for a while, u'll see how useful it'll be when doing cool flips and jumps. do the standing long jump for at least an hour 2 times a day. if u do this for at least 2 weeks, then u'r prepared to work on speed, endurance, and strength. the main important thing is to know ur limits. if u don't know ur limits, u may end up hurting urself. for example, if u do a wall run and u think u can sucessfully run 6 steps and u run and only do 4 but u continue running thinking u can make 2 more steps, u'll just end up with an injury. remember, if u rest from an injury too much, ur body will just end up wearing down and will have to get in shape again. so if u aim to get 6 steps, just stay small and stick to 4 steps. if u practice constantly, boost up the number of steps on the wall run by 1. flexability and shifting of ur weight is also an important factor. when u're in the air, u're gonna have to be able to move ur body fluently so u don't end up landing on ur head when u do a flip. take these factors and examples into consideration. hope my answer helped.

work on your total body coordination. for example! practice with hand stands, and hand walking. i found that when i started free running, if i landed a little off balance, i'd swing an arm around to try and correct it, and end up falling. work on your total body coordination, and these little mis-landings can be corrected using core muscles, such as your abs or back, which tend to be much more centered over where you land. eat well, rest up, and practice!