As a former rocket scientist, I have a soft spot for books about space. The Martian is among my favorites.

There’s a particularly memorable scene where the protagonist—astronaut Mark Watney—is giving a lecture to astronauts-in-training about the lessons he learned from being stranded on Mars:

“At some point, everything’s gonna go south on you and you’re going to say, this is it. This is how I end. Now you can either accept that, or you can get to work. That’s all it is. You just begin. You solve one problem. And you solve the next one. And then the next. If you solve enough problems, you get to come home.”

This monologue rescued me earlier last year when I set out to write a 90,000-word book.

Fewer things are more intimidating than staring at a blank document knowing you’re about to write Word 1 of 90,000.

Enter procrastination.

I really need another cup of coffee before I can get started.

Ooh, I think that’s my stomach talking. Let’s go get a snack before we start, shall we?

I haven’t cleaned my room in ages. Once my desk is clean, I’ll knock out the first 1,000 words.

Let me clean out my email inbox first and tackle the 10 items on my to-do list to give myself the illusion of doing useful things.

My sock drawer *really* needs to be reorganized.

And on and on.

All I had to show for my first week of writing the book was one crappy paragraph (and an impeccably clean sock drawer).

Then, for some reason, I thought of Mark Watney.

You solve one problem. You solve the next one. And then the next. If you solve enough problems, you get to come home.

I took an entire day and broke down that mammoth task of writing 90,000 words into its smallest subcomponents.  Each subsection of the book–however small it might be–became a separate to-do item.  I applied the same process to the research I’d have to complete to finish the book.

By the time I was done, that intimidating, seemingly unconquerable “Write book” goal became nearly 100 separate to-do items.  These subcomponents represented the small problems I’d have to solve.  Take that, Mark Watney!

90,000 words? That’s hell. One subsection of one chapter? That I can do.

I finished writing the book in 8 months (while maintaining a day job as a law professor).

You don’t have to be a fictional astronaut or a lowly law professor to apply this strategy.

Want to run 10 miles? Start by running one mile (which itself requires putting one foot in front of the other).

Got a huge PowerPoint deck to prepare for an important meeting? Begin by creating one slide.

Want to lose 20 pounds? Start by losing 2 ounces each day.

Want to work out regularly? Begin by doing 5 pushups every day.

After one mile, one slide, one pound, one push-up, others will follow. You’ll develop momentum. You’ll get a hit of dopamine for each problem solved and each item checked off your to-do list. And before you know it, the distance in front of you will be shorter than the distance behind you.

The small problems I listed above might appear too small for some readers. That’s the point. The more easily you can meet your goals, the less likely you are to give them up. IBM’s sales team used to have some of the best sales records, even though their quotas were much lower than their competitors. With low sales quotas, the team members weren’t intimidated to pick up that phone and start making calls.

Confucius had this figured out a long time ago:

The man who moves a mountain begins by carrying away small stones.

What mountain are you currently facing? How can you break it up into small stones?