Why make turbo discs?
Turbo discs take the place of starbursts and provide response and smooth string play. It is inexpensive and easy to make your own.

How do I make them?
Buy a roll of self-adhesive medical tape from a grocery store or drugstore. I use 3M "Durapore" tape, which is pictured here. The easiest way to cut out a turbo disc is to cut a square piece of the tape, then fold it in half and cut a square out of the middle. I don't see any reason to cut them in circles, other than aesthetics, and that would take a thousand times longer. Save yourself the pain and energy and just cut them square, they should play just as well. Place the turbo disc on the inside of one of the yo-yo halves, going around the bearing well. Put another on the other half if you want. Sometimes a full turbo disc is too much; in that case, try putting just one dot on one half. An applied turbo disc is shown here: