If you have a knack for a certain subject and live near a college, consider offering up your brain power and teaching skills for some quick cash. Grade school kids need help too, and parents pay better than college students. You can take this idea to the next level and scale by tutoring online. To be successful, you have to have a good grasp of the concepts but also be able to find a way to relate topics using real-world examples.
Krystal, I understand what you are saying, but I have made money selling pictures online, and I am no pro. I can get great pictures of wildlife, tropical landscapes, and many things that other photographers may not be able to get. Should I not do this, so that other photographers can? I am also trying to pay bills and run a household. It seems that raising prices could eliminate some of your future clients. I occasionally get calls because someone can’t or won’t pay $250-$500 for someone to take pictures of their family on the beach. I also give them the CD of all of their photo’s, which many photographers won’t do.
This is the best way to boost your earnings, as you have the most leverage at the moment that a company wants you but isn’t sure whether it can get you. Use that to your advantage in negotiations. Another benefit of getting a bump up when you switch jobs is that the percentage boost will be baked into all your future raises, elevating your lifetime earnings. Here’s how to negotiate your salary.
No matter what method you choose to make money online, understand that you might be able to make some money fast, but for the sizable returns, you'll need significant sweat equity. However, a year from now, you'll be happy you started today. Remember, time is far more valuable than money. Focus on creating passive income streams that will free up your time so that you can quit the rat race and focus on the things that matter. 
Great list. I have another to add that’s almost as easy to do as going for a walk! Provide a litter cleanup service outside commercial properties for property management companies. The work is done on foot using simple hand tools. I started this service in 1981 as a side hustle and quickly grew it into a lucrative full-time business that I still operate. I share my experience with others in my book, Cleanlots, as well as offer free support.