(Sorry for bad English, i hope you may understand with the help of picture)
Are you looking for a way to keep your Apple Pencil with your iPad? Here's my cheap way to do so.
What do you need?
(1) Shrinkable tube (about 20mm wide)
(2) Heat gun (if you want to make a grip for your pencil)
All you need to do is cut your tube to length 2.6 times of your iPad.
Then put one end to the other end of the tube until it forms a loop that can firmly attached to your iPad case.
The friction is strong enough to hold everything in place.
You can wrap your pen with the shrinkable tube and heat it with a heat gun.
The maximum temperature of my heat gun is about 130C, i've heated it for about 1minute, the pen is just fine. It won't damage your pen.