Testing out your idea for a new business before you quit your day job is always a wise idea. It gives you a chance to make sure you really enjoy working for yourself and that your business is economically viable, while still allowing you the financial security of a steady paycheck. It can be a great way to “test-drive” your entrepreneurial dreams.

That said, having a side hustle is by no means easy. In fact, one of the things it winds up testing, inadvertently, is whether you’ve got the dedication and motivation it will take to be an entrepreneur. If you can manage the stress of day job/dream job double life, chances are you’ve got what it takes to run your own business.

I side hustled for two and a half years before going off on my own, and I know how challenging it can be. If you’re currently working a side hustle, or are thinking of starting one, here are a few key things to keep in mind to keep your business (and your sanity!) from going under in the process:

Learn to Say “No”

Just as important as your to-do list is your not-to-do list. You only have so many hours in a day, and if you’re running a side gig, chances are you’re already stretching those hours pretty thin. Now is not the time to try to make everyone happy or be everyone’s friend; now is the time to know your limits and take a stand to enforce them.

Practice and become comfortable with phrases like, “I’m sorry, but my plate is full,” and, “I wish I could, but I’m booked up right now.” The key to saying no without sounding like a jerk is to keep it simple (no long, flowing excuses), express your sincere regret, and leave it at that. You have every right to set your own priorities—and if you want your side hustle to ever become a full-time hustle, you’re going to have to.

80/20 Everything

You’ve likely heard of the Pareto Principle: 80 percent of your outcome stems from 20 percent of your efforts. In essence, it argues that it’s smartest to focus your energy on the tasks that give you the highest return on investment. Everything else? You can probably get away with letting it slide.

This is true not only when it comes to your business, but also when it comes to the rest of your life. When you’re holding down two jobs, you can’t beat yourself up too much when certain things in your life fall by the wayside. Rather than trying to do everything, focus on just trying to do the essentials. Your house may be a little messy, but at least you can do enough laundry to keep your family clothed and enough dishes that you have something to eat off of each night. You may not be able to make meals from scratch, but try to get healthier takeout on the nights you’re crunched for time.

Schedule in Some “Me” Time

When you’re in full-on hustler mode, it can feel wasteful and selfish to spend time on anything that isn’t “billable.” (Believe me, I know.) But the harsh truth is that your business won’t last very long if you crash and burn out. If you can’t get yourself to take a break now and then for your sake, get yourself to take one for your business’s sake.

If it helps, schedule in time for yourself on your calendar just like you’d schedule in time for a project. Treat yourself as another client, and adhere to your assigned “me” time with the same discipline you’d adhere to a client deadline.

Trust me. It will be worth it. Hustling is ultimately a long game, and you want to keep yourself in working order.