Before we get started I'd like to take the opportunity to disclaim any responsibility. What is created here is to be used on a power tool, and power tools can be dangerous, so any accidents that result in the use of the custom sanding drum is not my fault. So BE CAREFUL! That's right, even if someone jumps up behind you, be ready, accidents (or incidents :D) happen this way too, I know from experience.
Start by cutting a strip of tape, about 7cm (3") long and wrap it around the drum bit sticky side out.
I use ½" wide tape; it's the same height as the drum and fits nicely.