I think this has been asked before but iv been trying sej flips for a while and cant catch the seat, if theres any1 else trying this trick please respond to this and the scares few that can do it as-well
Should post this somewhere else 
No one uses this part of the forum
to easy man just practice… haha jk i was actually trying them a couple of days ago and i found that the harder you throw the back of your seat the better it stays under you…
Hey will, I can only speak for outsejs, but I can tell you that I first had to learn how to move the seat without letting go for the whole 720 degrees. I usually only rotated it around 630 degrees or something, but after awhile I realized that I can sort of throw it like a normal 7spin and then let my hands stay on the seat to guide it, not to carry it. That’s how I get the full flip/spin.
Hmmmm buuut… Adrien and Shaun let go of the seat… Adrien landed his first seat backwards and fully let go. Then with sidesej he again fully lets go.