Companies like Uber and Lyft offer a great opportunity to make some quick cash. You'll need a clean driving record, a fairly new car and the authorization to work wherever it is that you live. If you have all of those things, you can work when it's feasible for you, whether that's in the middle of the day during rush hour, or in the wee hours of the night on a weekend. The choice is yours.
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.
If you need to make money really quickly, your best bet might be to sell something of value. For example, you can sell a piece of jewelry at a pawn shop or jewelry store. If you have an old smart phone or tablet lying around, you may be able to get instant cash for it from an ecoATM kiosk. Keep in mind that while these methods are easy and super quick, they won’t get you the best value for your goods.
If you’re strapped for cash but want to work on your own schedule, you might want to consider becoming a driver for Uber or Lyft. You can drive as much (or as little) as you want and set your own schedule. Plus, you get the added bonus of having interesting conversations along the way (or, at the very least, some fun stories to tell of your travels with strangers).