Hobbies are useful in that regard because spending money is really easy if I go somewhere. So I try to stay home. This works out most of the time because I like being at home. I finished making wash cloths today.
A yard of terry cloth wasn't expensive. I zigzagged the edges and tried to get the fuzzy bits off. The light creamy yellow is pleasant. I got a dozen wash cloths in a color I like, didn't spend much money, and it occupied some time.
When I don't want to spend money, it helps if I don't go anywhere. Seriously, I've sat in the car lots of times because I knew if I went in, I'd spend money.