These days, side hustles are really taking off. As of late last year, a good 44 million Americans had a second gig on top of their primary jobs -- and for good reason. Having a side hustle is a great way to build savings, pay off debt, and keep up with your living costs. But if you're not careful about how you manage your side hustle, it could come to compromise your primary income stream: your full-time job.

In fact, in a recent CreditLoan study, more than 20% of Americans admitted to having spent time on a side hustle during regular working hours at their main jobs. In doing so, however, they no doubt put themselves at risk of getting fired.

Man at a desk checking a mobile phone

Image source: Getty Images.

Even if you aren't caught dabbling in your side hustle at work, there are still consequences to be had. For one thing, if you spend too much time sneaking in that additional work, your output will suffer as a result. And that could hurt your chances of getting promoted or snagging a raise at the end of the year. A better bet, therefore, is to make a point of attacking that second gig outside of regular working hours only.

Managing your side hustle

The challenge in taking on a side hustle is finding the time to get all of that extra work done. But if you're strategic in your approach, you can make it happen.

First, be sure to plan out your weeks in advance. If you tell yourself you'll just wing it and squeeze in that extra work when you can, it's likely to fall by the wayside, so decide which nights or weekend days you'll be working, and when you'll be doing other things.

Next, take your social calendar into account when taking on side jobs. If you know you have a week with a bunch of personal plans, go easy on the work front and catch up another time. If you overcommit yourself, you're more likely to be tempted to sneak in side hustle work at your main job, and that's when you might get into trouble.

Along these lines, expect to spend less time on your side hustle during busy periods at work, and plan to ramp up when things get a bit slower. Telling your boss you can't stay late because you have a second gig to get to is a good way to lose out on whatever raise might've otherwise come your way, which will only negate your overall money-generating effort.

Finally, consider using your vacation time to work that side hustle if you have a major project to tackle or a period with a lot of demand. Of course, doing so probably isn't ideal, since you'd most likely rather use your vacation time for, well, an actual vacation. But if you're running out of hours to do that side work and want the extra income, you might consider taking a couple of days off here and there and knocking it out. This way, you'll reduce your stress load, and may even come to enjoy the fact that you just plain got a break from your regular job.

Managing a second gig is tough when you're already working full-time, but don't put your primary job at risk by working that side hustle during regular business hours. You're better off scaling back on that second job if need be and focusing the steady paycheck you no doubt rely on.