I covered my LIKE seat twice.
The first attempt was using very nice marine grade brown vinyl. As an amateur ulpholsterer I found this to be much too thick and hard to work with. ( there are posts from a couple of us - learn from our mistakes!) The second attempt was using this stuff from SailRite, the All-Sport 4-Way Stretch vinyl was much easier to work with. If I were to do it a 3rd time, I'd rent a power stapler and use this SailRite vinyl again.
My most important tip would be to: put the newly shaped foam on your scoot, cover with something.....and TEST ride it as many times as you need, until you are completely satisfied with its comfort. A week after you've completed this project you do NOT want to be riding thinking, "Shoot, I wish the seat had a little more here...." etc.
I took at least a 1/2 doz rides ----and when I was sure I had it - I extended that ride to 45 mins to be sure.
The black SailRite comes in smooth, and grippy. I chose the smooth - and am happy with that. It lets me move a bit on the seat if I want to - but does not toss me under the dash when I stop quickly.
Good luck, take pix, keep us posted.
You're gonna love your new seat!
Stig