There are a couple ways you can do it.
Personally, my favorite way:
-kinda just bike around in small circles 2 or 3 times,
-then bunny hop your highest,
-then you kind of have to use your arms to swing it, just keep your arms straight and just push them left or right,
-then kick (i mean push) the back of your bike to the way you want,
-the keep pushing until the 180 point,
-then to control your bike, force the handle bars down and let the back fall.
Extra tips?
Ya, always bend your head and look where you want to spin.
And if you want you can bend your hips and lean your bike over.
Try looking at some videos on youtube.
