My favorite sleeve is completely smooth and it’s impossible to hold in place just by strapping it down with the Handy strap. I take a sticky piece of hook velcro, cut it in half, and stick those two pieces together. Having hook velcro on the inside grabs the sleeve with friction, and the hook velcro on the outside obviously velcros itself to the Handy strap. It doesn’t have to go all the way around the sleeve. Then I hold the velcro in place on the sleeve with a fabric hair rubber band. You can use a regular rubber band, but the velcro will grab onto the fabric hair rubber band better. Additionally you can also put a piece of velcro on the Handy’s slide in order to grab the fabric hair rubber band that’s around the sleeve, but it might not be necessary.