Even if it’s a mundane task like walking dogs, you could start the next (or only) full-service dog walking and grooming service in your town (where dog owners rave over your business and always refer you to others). You can also hire other dog walkers as you grow, and turn your side hustle into a sustainable enterprise. You just have to do the work, and do it well.
Set up a roadside stand. Depending on where you live, you could profit handsomely by setting up a roadside stand. If you live near a resort area, for example, you could buy cases of bottled water, put them on ice, and sell them to passers by for twice what you paid. Selling fruit and produce you grow yourself is also a smart idea in highly-traveled areas.
Utilize websites like Payscale.com, Salary.com, and free salary guides from Robert Half and Randstad to find out what a competitive salary might be for someone with your expertise and education in your area. Document everything that you have accomplished at work in the past year and present it to your employer. When you are making an honest case for yourself instead of demanding a raise, your employer will at least consider your request.