me and a mate were trying them the other day. i can get my back wheel off but swinging it round is pretty hard – can only get about 30 degrees. what’s the trick?

Practice
Practice
Practice

And a bit of practice as well.

turn your head and look where you want to point, your body will follow.

practice. and more bodyweight usage. do a sort of backswing one way prior to the endo, then swing into it as you go onto the front wheel.

you need to turn your bars away from the way the back wheel is heading. If you are turning the back wheel to the right then turn the bars to the left.

Most of the work is done in the hips though, you just need to give it a good flick and commit to the move and you should be able to do 180 degrees without any problem. eg, i can do 180 degrees without any bother on my bmx, and that doesnt have a front brake, thus proving most of the action is in the twist of your body