At work, our days are pretty structured. We know what we’re supposed to be doing most of the time.

At home, though, things are looser. And our leisure time—the portion of the day that’s really, truly ours—tends to be the least structured of all.

This may seem like a good thing, but it can be a big problem. Without a plan, we tend toward passive leisure activities: activities that entertain us without requiring much physical or mental effort, like watching TV and browsing social media. A little passive leisure is fine, but many passive leisure activities are engineered to be addictive. They can grow to devour nearly all of our free time, leaving our lives a bit empty.

On the other hand, we have active leisure activities: those activities that require substantial mental and/or physical energy, like exercise, reading, meditation, cooking, writing, making music, gardening, and many more. Active leisure activities can sound overwhelming—who has the energy to run five miles or read Infinite Jest after a full day’s work?—but counter-intuitively, they tend to create energy. Active leisure activities help to give our lives meaning, too. See, we think we’ll be happy doing nothing, but it’s progress—not endless relaxation—that creates happiness.

But active leisure won’t happen without a plan. So if you want to use your free time productively, to make progress on projects that are important to you, don’t be afraid to plan it.

And there’s no better time to start than now.