How do you clean paper shredder?

Unplug it for safety, turn it upside down so that you can see the teeth/gears. Clean the paper bits out with a stiff brush until no more will come out. Plug back in and shred a small piece of paper so that the teeth/gears will be in a different position when they stop. Repeat the process until the excess amount of sticky paper/envelope glue has been removed. Tip: a few drops of sewing machine or light 'machine' oil on the teeth/gears will prevent paper and glue buildup. You can just oil a few pieces of paper and feed them through in different positions so that the whole length will get coverage.