LOOK at this first : http://www.youtube.com/watch?v=NpIc0xzA_bM 1:35 ... how should I train more efficiently to be capable in doing that out-of-this-world thing ?
I'd suggest getting someone to teach you. Doing Parkour is hard and from what I gather required a lot of muscle strength. Also landing techniques, accuracy, grip and lack of fear of heights is a must. Personally I wouldn't be able to do it.