Bedding for worms is thankfully not what I consider bedding. Bedding can be any shredded "brown" material like shredded newspaper or computer paper, coir, wood chips or peat moss. Just as with outdoor composting, a balance of green and brown material is necessary for proper decomposition -- also, and more importantly, a proper amount of brown material keeps the green material from getting stinky.
The Can-O-Worms comes with one block of coir, or coconut fiber. To loosen up the coir, I soaked it in a bucket full 3/4 with water. I left the paper wrapping on the block -- paper is prime food for worms. After about 15 minutes, the coir had become a brown mass of mush. I scooped up handfuls of coir, squeezed out excess water, and spread it on the cardboard packaging on the bottom of the working tray.
Different beddings have pros and cons. Shredded newspaper is easy to obtain, holds moisture well, and doesn't have an odor, but it can also become matted and thick easily. Machine-shredded computer paper is also easy to obtain but it doesn't hold moisture as well as newspaper. Coir is apparently a byproduct of the coconut industry in Sri Lanka, and the islands started exporting it as a substitute for peat moss as a way to handle disposal. However, knowing that coir has to travel long distance (I don't have the same information about my newspaper or computer paper) and seeing the cost, I'm not sure I'll use it again, even if the worms seem to love it.