Another method, guerilla testing, worked well in grad school. Go to a public place - a library, coffee shop, etc. Politely ask random people to test your project. The obvious downside is they may not fit your target audience, but it's a cheap and scrappy way to get some feedback.
Where do they hang out? That's probably a good place to start.
2) make threshold to test the product and post feedback low (e. g. GitHub)
3) promote it on HN, reddit, producthunt...
4) people will test and some will report bugs / submit ideas etc.