here how you do it
Begin by riding at a medium/slow pace with both feet on the back pegs.
Take your right foot off of the peg and while turning the bike slightly to the right swing your leg forward and then in a clockwise circle behind you while pulling up on the handlebars. To get the feel of this correctly most people say is the hardest part!
When your right foot comes behind you the bike should be coming up and the bike should already be spinning in a circle to the right. Keep your handlebars turned to the right and keep pulling it upwards towards you.
There will be a point when the bike hits its peak and the back wheel will want to shoot out from underneath of you. This is the point where you put your right foot on the rear tire and pull down HARD with it- (at the same time twist your handlebars slightly to the left).
If you have done this correctly the bike will be in a tight circle spinning backwards. Now comes what is TRULY the hardest part of the trick… Keep your momentum by continuously pulling down on the back tire. If the bike should go forward instead of backwards or if you need to grab the brakes you probably are going to be done with spinning.
How hard you pull down on the tire and how much you are leaning are the determining factors of how well you will spin. When you are learning the trick much of your spin will be determined by how well you ride in. Soon it will be by how well you are able to pull down on the tire in the spin and lean the bike correctly.
To ride out let the bike loop around forward and grab the brakes hard (if necessary) to bring the front wheel to the ground. When you get good at this you will just let the bike spin from backwards to forwards and coast in a wheelie out of the trick or into another trick.
This is another one of those tricks that is a little more advanced and needs to be built up to. Don't expect to do ten spins the first day that you are trying the trick. What you should shoot for is getting the feel of throwing your right foot in a circle and having the front end come up. Then work on grabbing the brakes and having the frame spin around. Finally work on pulling down on the tire so that the frame keeps its momentum.
You will quickly learn what it means to pivot on the back tire. It is the point at which the bike stops leaning to the right and traveling forward and starts leaning to the left and traveling backward. Understanding how and when your bike will and wants to pivot is key to mastering the mega spin.