A good 44 million Americans today are supplementing their regular income by doing additional work on the side. For some, it's a means of getting their hands on extra spending money. Others do it to build savings or pay off debt. But while taking on a side hustle can be advantageous from a cash flow perspective, managing a second gig on top of a primary job can be challenging. Here's how to excel at your side hustle without driving yourself crazy.

1. Plan your weeks ahead of time

Working a second job into your schedule isn't something you can easily do on the fly. Rather than wing it, map out your weeks in advance so that you know when you're supposed to be accomplishing various items on your never-ending to-do list. For example, maybe on Monday you'll work at your side hustle, but then run errands on Tuesday and catch up with friends on Wednesday. But if you don't define what you'll be doing with your time, your side gig might fall by the wayside.

Man at a laptop in what looks like a living room

IMAGE SOURCE: GETTY IMAGES.

2. Take on more side work during slower periods at your main job

It's hard to manage a side hustle when you're already clocking in 40 hours a week, and often more, at your main job. That's why it's smart to take on extra side work when things slow down at the office. If you're a tax professional, for example, you're likely to find yourself swamped between January and mid-April, so the spring and summer months might be a better time to do your freelance artwork on the side. The key is to get your timing right so you're not letting your clients down or burning yourself out.

3. Eliminate distractions

When you're working in an office, it's harder to slack off when there are people around you watching your every move. But if you're doing a side hustle from home, what's to stop you from turning on the TV for what you think will be just a few minutes and getting sucked into the latest reality show that's playing? If you're going to succeed at a side hustle, you'll need to be careful about not falling victim to distractions, so set rules: No TV until your projects are complete, no checking voice mails or texts until you've put in at least an hour's worth of work, and so forth. Better yet, hide your mobile phone and turn off the ringer while you're working your second gig so the temptation goes away.

4. Make sure you're doing something you love

When you spend your days plugging away at your main job, it's natural to want to come home and enjoy some downtime. That's why it's best to find a side gig you genuinely enjoy doing -- so that it doesn't feel like work but, rather, a hobby you're able to turn into cash. Incidentally, you might also come to be more productive if your side hustle is something you actively want to be doing with your time, as opposed to feeling like you're torturing your mind after a long, hard day at the office.

Succeeding at a side hustle requires hard work and lots of sacrifice. Your reward? An opportunity to enjoy some extra cash that can help you meet your financial goals or better enjoy your life. And that's reason enough to keep at it.

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