You might want to try a few different craft ideas before you find the one that you like and that will bring in additional income to you. Start by experimenting with jewelry. There are many kits and easy pieces to make. If you like to sew, pillows and aprons are easy projects for selling or as gifts.
I would take a look at making and selling handpainted yarns. It is a very easy craft to learn with a very high demand. The supplies are easy to find and can be inexpensive... natural yarns, fiber dyes, and gloves!
