For red wigglers, the best bedding is a 50/50 mix of shredded black and white newsprint and coconut coir. The bedding should be the dampness of a wrung out sponge. They will die if the bin is wetter or dryer than a damp sponge. Add crushed garden lime (dolomite, not hydrated or slaked) every two weeks, to keep acidity under control in your bin.
It's best to start feeding with chicken egg layer crumbles or plain cornmeal. Lightly surface feed these grains, and do not feed more than the worms can eat in a few days. As the population grows, you can start feeding vegetable scraps. Avoid citrus, onions, dairy, and meat products. Also spicy and salty food scraps should be avoided, as these can kill your worms.
If you are noticing that all of your worms are staying small, then it is time to start a new bin. These worms reproduce quickly, which causes them to stunt. Take out half of the material and worms from your old bin, and start a new one. Keep on expanding as space allows, or go fishing more often!