If you have anything you don't use anymore, and it's too large to sell online, Craigslist should be your go-to place to sell stuff. In college, you may want to sell all your furniture before moving home from school at the end of the year. Depending on what you own, a few $100 might be better than storing it or transporting it back with you. It's easy to setup a listing and sell anything on Craigslist.
Are you an interesting person or do you do a cool job? People are always looking for interesting people to officiate their weddings, and you could get paid for it. For example, if you're a skydiver who officiates weddings, you could get paid to host a sky diving wedding ceremony. Since most pastors don't do these extreme sports, it's a great side income for those that do.
One of the many difficulties faced by students when looking for employment is the lack of experience. You can, however, still use your knowledge to earn some money by teaching your juniors. You can give online tuition on Skype to earn money. Or, you can provide tuition to your juniors at school or your neighbors. Lots and lots of people are doing this to cover up their personal expanses. In some cases, learning from senior is easier than learning from teachers, which is why a lot of parents send their kids for tuition. Students who cannot access the service at school can opt to unblock Skype with a VPN.
Reselling textbooks — This is a great way to bring in some money. When you’re done with a textbook, see how much it’s going for online. You can even compare that price to what the booksellers on and around campus are offering, and see which one gets you the best deal. (Buying used textbooks online is also a great way to keep more money in your pocket each semester!)
Now, this is for students who have a strong desire of entering the entrepreneur world, one can begin a startup of his own with a group of people or alone. Many students did start their businesses in their college life. This can either be a success or a lifetime experience. Developing an Android application is the best form which has even made people millionaires. You can also begin with the website development, or there are various programs being held in colleges which involve interaction betwixt students and businessmen, who aspire to learn about idea students, have and do pay for a good business idea whilst making an investment into the same. Getting associated with a startup also works well, taking an instance from my own life, I got into Business Alligators in my second year of graduation.
Barter your services with friends. Do you spend more than you'd like getting your hair and nails done each month? Do you have a friend who can't resist the pastries at the coffee shop or who pays for a personal trainer? Think about what both you and your friends spend money on, and then see if there's a way for you to barter and trade services with each other in order to save money.