Work and life demand much of our time. Finding time to be creative can be very difficult. Build and hold a routine, and hold yourself to it with military optimism. You will win the war, if you work hard enough. But what to do with that time you set aside?
There's a talk on creativity from John Cleese on BrainPickings in which he outlines the circumstances that most often lead to creativity. I recommend the video, but in a nutshell, he mentioned 5 necessary elements. We need an oasis of space (1) and time (2) (ideally 90 minutes) in which we are cutoff from everything else. We need time (3) to tolerate the discomfort of not-having-reached-the-best-solution-yet (i.e. don't take the easy way out). We of course need confidence (4). And, lastly, humor (5), which he sees as the fastest way to step from closed- to open-minded thought patterns.
For me, finding the time is all about fighting two things: priorities and procrastination.
For priorities, John Cleese (and many others) note a huge difference between things that are important and things that are urgent. When you finally have that time, do what is important, not what is pressing or easy. Do the big ones. Don't be intimidated, don't put off a big project just because a little one is easier.
Procrastination is the enemy of the mind and soul. Defeating procrastination is all about doing it right now. Pump up your self-control and your will power. It's hardest to defeat the first time. And once you've done that, it's not quite as hard the next time, but soon you've got a habit, and then you're golden. What are you doing right now? Why are you doing that thing that you've always wanted to? Why aren't you writing that story you're thinking about? DO IT RIGHT NOW. You'll be happy you did.