Taking care of yourself is not a luxury. It’s a necessity. Study after study shows the importance of eating nutritious meals, exercising regularly, and getting enough sleep. And there is a wealth of research proving that your mental and emotional well-being is just as important as your physical health. Yet self-care is often the first thing to go when life gets busy.

Let’s be honest, self-care can feel, well, selfish—or like something only “weak” people need. For me, taking time to stretch or lazily read a novel would feel amazing in the moment, but I often found myself distracted and unable to fully enjoy it. Why? Because in the back of my mind, I was berating myself for not working on my latest project, catching up on email, or doing another load of laundry instead.

In other words, I was focusing on doing at the expense of being. Then, I had an “ah-ha” moment: My to-do list isn’t going to change anytime soon, and I’ll be busy for the foreseeable future. If I don’t take care of my own needs in the short term, there’s no way I’ll be able to thrive in the long term.

Here’s how to fit self-care into your life, no matter how busy your schedule may be:

1. Think of Self-Care as an Investment, Not an Indulgence

An important public service announcement: Putting yourself “first” does not mean that everything else has to fall to the wayside, or that you’re weak, or that you’re selfish. It means that you are taking the time to attend to your needs and refuel…which is human, and ultimately will help you do a better job at taking care of everyone and everything else.

Shift your perspective by reminding yourself of what self-care accomplishes: It helps you beat burnout, stay engaged at work, remain present with your family, and feel less anxious.

2. Focus on How You Feel

Do you find yourself relentlessly tracking your downtime activities, like sleep or exercise? Wearable devices are wonderful, but they can also blur the line between self-care and self-obsession. “People become overly fixated on the system that they’ve set up to keep themselves accountable, and when they don’t keep up the systems, they feel worse than before,” says Jessica Slavin Connelly, a psychotherapist who often works with clients on body-image, anxiety, and self-esteem issues.

Instead of attaching a number to your goal, attach a feeling. Ask yourself: “What’s my vision for how I’d like to nourish myself? What does a week look like in which I feel good?” Connelly suggests.

3. Say Yes to Sleep

Stress keeps our bodies awake and alert—so when we’re stressed, we’re less likely to get a good night’s sleep, and research shows that many people lose much of their sleep worrying about sleep itself. (Ironic, right?) Focus on getting the right amount of sleep for you by tracking your sleep quality and quantity for around a week. You’ll know that you’ve hit your sleep “sweet spot” when you wake up feeling rested and ready for the day. Use this number to figure out your ideal bedtime.

If you have a hard time reconciling ambition with relaxation, frame sleep as a way to feed your productivity: If you don’t sleep well, you can’t effectively problem-solve and you’re vulnerable to stress—making it that much harder to achieve your goals.

Kara Baskin is a Boston-based journalist and well-being expert. For over 15 years, she has been helping consumers live healthier, more fulfilling lives, writing for outlets such as The Boston Globe, Time, and Women’s Health. Kara has also collaborated on several books on women’s health and resilience. Find her on Twitter @kcbaskin