I've written before about the challenges of working full time and writing on the side. I'm hardly the first person to broach the subject. Full-time fiction writing is extremely difficult, to the point where, out of all the writers with whom I'm acquainted, only one has managed to do it (his name's Travis Thrasher, check him out).
Previously, my strategy was to write during my commute. Since I had an hour-long train ride every day (both ways), that added up to a pretty decent time to focus on writing. When our offices moved, however, my hour-long train ride became a half hour. That led to much less writing time, and eventually to me not writing on the train at all. The fact that I gave up is on me -- half an hour is better than none-of-an-hour. But regardless, I was down to basically no writing every day.
That went on for longer than I'd like to admit, so I won't.
My strategy today is one I stole from somewhere, and I regret not noting the source because it's been working wonders so far and I'd like to thank whoever it was who came up with it. The challenge I read was to dedicate yourself to writing a page a day all throughout the month of October. There was no specification as to whether that page should be single- or double-spaced, so I decided to add a bit of extra challenge and go single.
It's no NaNoWriMo, but I'm a good 10,000 words into my next piece, and that feels great. One page every night after work doesn't feel like an unattainable goal. And even having a goal is incredibly helpful for me. Back when I would just write a nebulous amount "whenever I had a chance," I never made the sort of progress I might have wanted to.
If a single-spaced page is too much for the amount of time you have, try a double-spaced page. Or a paragraph. If you're into word count, pick something you can stick to. 500 words. 1,000. Ultimately, I think it doesn't matter so much what your goal is, so long as you have one and stick to it.
So, I have no revolutionary advice. I'm sure I've read articles similar to this extolling the virtues of the same or very similar advice. But I guess I never paid them much attention until I really tried to do it for myself. It does work.
This next part might be controversial, but hear me out.
As part of your daily writing exercise, resist the urge to edit.
That means don't reread what you wrote the previous day. Don't reread any of it (unless you need to remember a specific detail for a scene you're writing today).
I'm a notorious editor. I can't leave a piece alone. I was making edits to my novel until about a week before it went to print.
So writing a first draft is a special kind of torture to me. Because it's not just something I've written that I want to make better, but it's the first draft of something I've written that I want to make better. First drafts are poopy. That's what they're designed to be. Let them be poopy. There will come a time when you can weave that poopy into gold, Princess and the Pea-style.
It's a challenge, but it helps me make efficient use of my limited evening time.