Have you ever thought about holding a garage/yard sale? I don't know where you live or anything like that, but if you want to make a little extra cash, try selling some old clothes, books, and other things you don't use. It's a good way to earn a bit more money.
Another thing you can do is do lawn services in your neighborhood such as mowing the lawn, raking leaves, washing windows, watering plants, shoveling snow, etc. You don't have to make it a full grown business - just enough that you can do some tasks for your neighbors and get paid to do it.
Also have you ever considered babysitting or pet sitting? They make a lot more money than you think. You can charge a good amount of money per hour for this kind of labor, but also don't charge more than other local sitters, pet carers, or daycare facilities. If you do, people are more reluctant to try to hire someone new.
Those are just a few ideas. I mean you could also get an actual job, but that's not exactly a quick process. Good luck!