You gotta hustle, hustle, hustle. As a fellow college student, I feel your pain. I have to figure out ways to make money too. Let me tell you someways I've made money.
Get a job! This is a super obvious answer but this should be your most important priority. I have two jobs this summer( CareerVillage and Abercrombie) and I work one (Abercrombie) during the school year. If you're not taking summer classes, work more hours try to earn as much money as possible because you have more time! Even try to get a 2nd job if possible! I will be real with you its not the most glamorous lifestyle but do whatever you gotta do make money!
I've done reselling! What do you know best? Do you know books, guitars, shoes, fashion, etc? Buy items you are interested in and resell them for a higher price (amazon, ebay, facebook selling groups, etc.) But make sure you know other people will buy these items. Ex. I love raves/concerts and I often know which ones will be sold out real quick so I wait in line at the venue and buy the tickets for face value. I hold onto these tickets for a week or two and then sell them for 30-60% more than I paid for. If you have a good grasp of the concept of supply and demand you can do similar things! Also watch this video its super helpful this guy, Gary Vaynerchuk will teach you how to hustle. https://www.facebook.com/gary/videos/10154161437813350/ also watch his other videos he drops so much knowledge!
3.What skills can you do? Are you good at certain topic? Go ahead and tutor other people! Can do you do photography ask around/put an ad out about yourself and do some gigs, can you knit beanies go ahead and sell them to friends/contacts.
4.Also if you have used items that you don't want anymore( electronics, clothes, etc) go sell them and make some extra money.
I'm pretty sure there are more ways to make money, its amazing what a simple google search can do. Don't look for that "easy money" its not going to help you in the long run, you got to put in the time and effort. A lot of the time it wont be easy but your hard work and efforts will pay off! I hope this helps you! Feel free to leave a comment if you have any more questions! -Ben