Wind up the same way, as you would for cartwheels or aerials.
Kaydem
The kaydem is a blasterscoot without hands. You can also view it as an aerial, where your jumping leg doesn’t leave the ground.
Just like the blasterscoot, the kaydem is a great setup move for tricks that takeoff in backside stance.
Spot the ground and lower your upper body. Get ready to swing your backleg up.
Swing your backleg up high and pull it around.
Pull the swing leg all the way through and use it's momentum, going downwards, to lift up your upper body.
Quickly stand out of the kaydem, when both feet are planted.
Push through all the way to get as much height and power as possible for the next trick.
Tips
It’s a little bit easier to maintain balance, if you swing your leg more vertical instead of to the front. However it requires more flexibility.
Because you can't use your hand to push yourself up again, you'll need to be a little bit faster on the kaydem to generate momentum from your swinging leg and basically catapulting your upper body up.