Whether you're behind on emergency savings or are simply trying to round up some extra cash for a new purchase or vacation, you may be one of the 44 million Americans who currently work some sort of side hustle. Taking on a side gig can be a great way to generate extra income, especially if, despite your best efforts to trim your budget, your regular paycheck tends to fall short. In fact, of those who have a second job, 36% earn more than $500 a month in extra money as a result.

The problem with a side hustle, however, is that you may reach a point where you're pretty much working all the time. And that could affect not just your mental health, but your physical well-being as well.

stressed young woman sitting at desk in front of laptop with her face in her hands

Image source: Getty Images.

Consider this: An estimated 40% of U.S. employees work more than 50 hours per week, and 20% put in more than 60 hours each week on the job. If you're already spending the majority of your waking hours at your regular job, and you then attempt to squeeze in a side gig, other aspects of your life are apt to suffer, whether it's relationships, exercise, or sleep. With that in mind, here are a few tips for managing your side hustle without completely losing yourself in the process.

1. Find a side gig you truly enjoy

Our brains can only handle so much before we start craving a mental break. But if you find a side job you love doing, that extra gig may not seem quite so much like actual work. Say you're a marketer by day who dabbles in graphic design for fun. If you're able to monetize that hobby, you'll get paid for something you'd probably do in your spare time anyway. Similarly, if you're an animal lover and can moonlight as a dog sitter for folks who go out of town, you may not mind putting in the time.

Depending on what it is you want to do, there are numerous online resources for finding additional work. Sites such as Care.com allow you to search for openings in the babysitting (and pet sitting) realm, while Upwork is a terrific resource for freelance openings. Snagajob is another place to look if you're seeking a local hourly or temporary gig.

2. Limit your hours

If your side hustle proves lucrative, and you have the ability to pursue it for as many hours as you choose, you may be tempted to push yourself to the limit and fill your spare time with that extra work. But that's a bad idea, because even if you are doing something you love, you might quickly reach a point where it becomes overkill. Tempting as it may be to work, say, 20 hours a week on top of your regular job, if doing so leaves you with absolutely no downtime, you're better off limiting yourself to half that amount. Otherwise, you risk burning out, quitting that second gig, and losing out on the extra income you were previously generating. Worse yet, overdoing it might affect your performance at your main job, thus putting it at risk, too.

So how many hours of work is considered too many? One study found that exceeding the 39-hour mark could negatively affect your mental health. Of course, given that many jobs require more than 40 hours per week, sticking to that 39-hour limit may not be feasible, even without a side hustle. But if you are going to exceed that threshold, pay attention to warning signs that you're pushing yourself too hard. These signs include not getting enough sleep because your work schedule doesn't allow for it, not having enough time for personal care, and feeling overly stressed or even depressed as a result of your demanding schedule.

3. Write down your financial goals -- and give yourself a break when you reach them

Maybe you're working a side hustle to help save for a down payment on a home. Or maybe your goal is to pay off your credit card balance and move forward with a clean slate. No matter your reason for taking on that side gig, it pays to establish the goal it's helping you reach, and then reward yourself once you finally reach it.

Say you're aiming to sock away $5,000 from your second job to knock out your student loans and free yourself from those pesky payments. Once you hit that goal, consider scaling back the amount of time you spend doing that side job or, if your finances are in otherwise good shape, abandoning it altogether until the need for extra cash arises. While earning more money is a responsible thing to do, life isn't just about work, so don't hesitate to give yourself a break once your primary goals are met.

One final thing: If you come to find that your side gig is affecting your performance at your regular job, it's time to think about cutting back or quitting it altogether. While earning more money is definitely a plus, the last thing you want to do is compromise your main source of income in pursuit of a little extra cash.

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