bigger air, pop...

Hi guys,
i have a problem with bigger air / pop.I don't understand HOW Murrey, for example*because i've seen his clip, but many others do the same* ,when he is going toward wake, how he has rear leg that deep in the water?Please compare his clip from you tube,with mine...You will see that my board is not even close to the position he has.My board engle is almost flat, while trying to build edge.
I tried ,but i don't know what exactly should i do...and he is saying that "both legs, same pressure"...kinda strange, because rear leg is much deeper...?
I clear W2W ,but i am not satisfied with the height.Any help will do, thanks
p.s.i know i should "lock legs and be tall"...but still...
also,help with backroll....any suggestions,thanks
his clip
https://www.youtube.com/watch?v=pXa6lmilQrI
*its actually for raley, but i want air like here...
my clip

https://www.youtube.com/watch?v=awww...ature=youtu.be

thanks