just do it how you think you would wheelie
you cant realy explain, and if you go slipping the clutch when you dont know what to do you will end up on your arse
its just a case of getting your weight back and balancing the bike because you cant power wheelie for a long way on a pit.
A power wheelie is a wheelie where you are not at the balance point its the acceleration of the bike what keeps it up
but just get use to the feeling of the front in the air first by douing little ones.
when you get use to it you can change gear in a wheelie you just wack it through without the clutch but its easy to flip off the back when douing that. I have done it too many times
it broke the footpeg mount in 2, the rear mudgurad the rear mount on the seat and both the middle mounts on it aswel. lol that was me trying to change from 2nd to 3rd in one