How do I break into keeping books for small businesses?

When I owned my own business I became proficient in QuickBooks, which is a book keeping program designed for small businesses. My account said that knowledge and skill would allow me to start my own business someday, keeping books for other small businesses, but I would have no idea where to start.

Like, would it have to be local businesses only, where I’d go around picking up the receipts and cash for the day or they’d bring them to me? Or….I don’t know! I guess I don’t know how to specify what I’m asking. Is there someway this can be done on line? If so, how?