Having a Routine for Creation
I recently read an article on turning music into a chore where the author explains how he transformed the process of making music into a repeatable routine of archived chunks of work. A major factor for success with this method was the introduction of time pressure and collaboration as well as saving session results as wav files.
By timeboxing your sessions, you create an artificial deadline which may help in focussing your efforts to a greater extent. In line with Parkinson's law - "work expands so as to fill the time available for its completion", you will take five hours to finish that mix if the time you allocated for it is five hours. You will take two hours, if you've only got two hours.
When you collaborate with other people, you increase the amount of feedback you receive as well as the ears that listen to your work. You feel less alone in your struggles, you'll be able to get help for different problems that may arise and with each feedback cycle you'll see yourself making progress.
And by conveniently saving your output as wav files, you create the opportunity to quickly get back to products of your own work without opening your DAW, essentially creating your own royalty-free library of samples you can go back to whenever you feel stuck at your current project.
Of course, these points don't just apply to making music, they're valid in many other domains as well. In essence, what all these factors are contributing to is preparing yourself for luck, or in the words of Seneca:
"Luck is what happens when preparation meets opportunity"
So, having everything ready for creation, making it as easily accessible as possible, creating at least something you can get back to at a later date, all these actions will be useful when the right opportunity arises.
However, there is one additional element which the above suggestions wouldn't work without: showing up everyday. It is only when you consistently work at something that you can even begin to get better at it. The timeboxing will only bear the right fruits if the task at hand is somewhat learned and its individual steps are clear to you. The sample library can only be filled when there are samples to go from, tracks will only get finished if they're being worked on. That's obvious I can hear you say and yes, it really is! But just like Siddhartha had to go through a whole lifetime on his own despite being tought by the most knowledgeable people around, many things we cannot be told, we just have to do and experience.
We tend to overestimate how much we can do in one day, but underestimate how much we can do in a year, let a lone several years of constant practice, even if it's just for an hour or so. And yes, there is little time in a day if you have a tight schedule, a day job, a family etc. However, not having 30 to 60 minutes a day is less a thing of not actually having the time and rather one of low priority.
If you look at your daily habits, I am sure that there are distractions, vices, or means of consumption that you could at least cut for some minutes. Just having your phone in another room may lower the possibility for distraction while having a notebook or one-job recording device at hand (i.e. no phone or pc with copious other apps) may increase the potential for production, capturing thoughts, work, ideas, or whatever it is you're working on.
In addition to that, spend some time analyzing or at least thinking about your routine so you know when you are tired (e.g. if you need downtime in the evening, maybe try to get up 30 minutes earlier and use that time). What I am saying with this: for a dedicated, or with Seneca, prepared mind, there will be ways of incorporating a creation-focused routine into your day.