Can you pick up under the table jobs, like dog-walking or pet-sitting (assuming you like pets)?
Mow lawns, do small labor jobs for elderly or busy neighbors? Baby-sit (and use your psychology degree on the kids)? Elder care/companionship? Craigslist is sometimes a good resource to find these gigs, although of course be wary of meeting new people, use a public space, etc.

There are also free online college classes available. Just an example, there are many more: https://www.edx.org/school/harvardx

At the very least you can say you're taking classes at Harvard. Good luck.