I missed the northern lights on Friday night.

It’s incredibly rare for us to have that kind of light show this far south, but people in my town got some fabulous photos. Friends in a nearby town said they went outside several times to watch, to no avail, but they too had neighbors who posted amazing photos.

So I guess it’s all about being in exactly the right place at exactly the right time.

Timing is enormously important to much of life. This, I think, is one reason it’s important to take advantage of opportunities when they arise: because they may not come around twice. I looked outside to see whether I might get a glimpse of the northern lights tonight, but the cloud cover is solid and the predictions are that this time, the northern lights will no longer be visible here in southern New England.

Unsurprisingly, I’m thinking about how fortunate I am to have had the opportunity to do my writing challenge. At another time, it might not have been feasible, but tonight marks six weeks of daily work on my new novel, with no fewer than 1,000 each day written.

Even more exciting is the way the story has taken up residence in my brain, with new ideas percolating at unexpected times. This afternoon, as I drove on the highway to a Chinese restaurant to pick up Mother’s Day lunch, a thought came into my brain. Since pulling over and writing it down wasn’t an option—and I wasn’t willing to trust my brain to retain the idea until I could—I ended up calling my home number and leaving a message on my voicemail. And it was a good thing I did, because by the time I got home, I’d completely forgotten what the idea was.

(This is why all writers should abide by the recommendation of the brilliant Anne Lamott, who says that she always carries index cards and a pen in case she has an idea. In one of her essays—I don’t recall which one—she expanded on this, saying that if you get a great idea and you don’t have a way to write it down, God is going to give it to her instead because she has an index card and will make a note of it. Although these days, I suppose a voice memo or note on your phone will also suffice. The point is not to lose the idea. Whatever method you can use is okay, as long as it works.)

If you’re considering assigning yourself a challenge—and it needn’t be 100 days, or 50 days, or even 20—probably the best advice I can give you is to fashion a routine, which does mean it’ll have to be long enough for you to get into a routine. Whatever you’re doing, do it at a regular time and place. If possible, find an accountability partner, whether it’s the cat who curls up next to you every night or the friend you text every time you turn the next corner. If you’re gearing up, but you figure you won’t be ready in the next few weeks, I encourage you to take up Jami Attenberg’s #1000daysofsummer, which was the basis for my original challenge. Her challenge lasts only fourteen days, and there are crowds of people online who will cheer you on, share their own stories, and inspire you every day. Plus, if you want to keep going afterward, nobody’s going to say you shouldn’t. (Especially not me.)