I think paper products are often forgotten in a worm bin but they really help regulate the moisture.
I usually use shredded newspaper at the bottom of the bin as bedding. Some sites recommend wetting the bedding but I haven’t ever had to. Usually I add bedding once every 4-6 months when I notice the bin is particularly wet. I’ll roughly push the compost to one side and rip up some newspaper for the bottom. Then push the compost on top and add newspaper to the other side and even it out again.
I also put all my food waste in paper bags as I’m collecting it and put the paper bag in the compost. I like this method because the food breaks down and dries out a bit while collecting and makes it a bit easier for the worms to digest.
I also add paper egg cartons and toilet paper rolls in tact on top of the compost to cover the compost but allow for air circulation then top with a sheet or two of newspaper. I find the newspaper helps prevent red mites from breeding and crawling out of the bin.
Don’t worry, the red mites die almost immediately when they leave the bin but it does leave a lot of little red specks just outside your bin. I’ve found this usually occurs when my bin is too wet and there’s no newspaper on top.