I'll tell you one thing. Being an independent musician with a few other significant full time jobs (father, husband, podcast producer), finding time to sit down and focus on writing music can be a big BIG challenge. I'm certain you know what I'm talking about.
When I've gone too long, it becomes that thing that I have to do, and not necessarily in a good way. "I must sit down and try to work on new music tonight, cause I haven't for so long, I'm afraid I might not know how to do it anymore. And if music is so important to me, then it should be easy, right?"
My experience has told me that writing because I feel like I have to is a recipe for certain disaster. It's like taking that thing you love, and setting a 200lb weight on the top of it, saying "ok, lift for two hours. Go." Doesn't sound like much fun. And creativity is rarely sparked by rules and schedules. You either have something, or you don't. Or you don't, but your mindset is such that you're into the thought of experimentation until you DO in fact have something. In other words, you don't, but you know how to get there.
When I embark on a new album, I consider it a project with an end point. I don't look at it as "oh, I'll wait until the new year and then start a diet and see how it goes" or "I'll quit smoking next week.... Or maybe the week after that, cause I'm going to the bar next weekend."
If I'm writing material for an album, I've made a decision that the next X amount of time will be full of a lot of time spent doing the things I normally do (father, husband, job), as well as SOMEHOW making time to write, and staying devoted with that effort. Life can get crazy, but if you let yourself slide, who knows when or if anything you write will even see the light of day.
So, I set a goal. I might not know the date on a calendar when this album will see its release, but I know roughly a time at which I'd like to see it happen. Six months from now? A year from now? Doesn't really matter what I pick as long as it's realistic. Make it too short and you set yourself up for certain disaster. And in light of my other jobs in life, I still have to actually find the time in my schedule to allow all of this creative stuff to happen. Nothing wrong with setting a date far out in advance, and then finishing before then.
This next part is what makes setting a lofty goal like this a possibility with everything else I have going on in my life:
Evaluate the times during which you are alone, and the times during which you are in a house full of people. This can guide you in how you plan your sessions. Here's what I mean.
Alone time is tracking time. If I have a song with lyrics that I've finished, and a scratch track foundation for the song in Pro Tools, and I know that Wednesday afternoon from 3-5pm, I'm home alone before my family arrives, this is perfect tracking time. So I set it. And that's all I do during that time, unless I'm incredibly efficient and am suddenly left with extra time to devote to something else. But basically, if it's time by myself at home in the studio, it's the time I get to do the really loud things that are sure to disrupt the other bodies in the house. Or maybe they aren't disrupt-able, necessarily, and don't care when you turn your guitar amp up to 11 to get that nice feedback effect in the song your working on. It's still a distraction to me to think about anyone else around when I'm doing loud things. I consider this the time I do things like track vocals (lot's of layers and multiple takes of each), amped and acoustic guitar, live percussion, and much later in the process, mixing.
Occupied time is editing time. About 3-4 nights a week, I work in my studio from 9-Midnight, late hours that don't constitute my ability to scream a layer of vocals, or record that acoustic guitar track. This time is purely dedicated to arrangement, refinement of already tracked elements (like with vocals, I do a lot of alignment during this time), synth parts, and pretty much anything programmed like drums. All of that can take place without compromise inside headphone land.
Now, if I've played my cards right, I've tracked to my hearts content during those two hours in the afternoon, more than I actually need. (Hence why I recommend you track every vocal part 2-3 times and keep all of those takes) Then, when I get to my evening session, I have an overabundance of options for each part to pick from, based on whatever it is I'm working through. I don't want to think "dang, I didn't get this part today" and then have to wait until my next open slot during the day time to record it. I mean, I will if I have to, but I'm an instant gratification kinda guy. So I want those parts there when I've blocked out time for editing them.
It's all about plotting your open time efficiently to the material you are working with. Boy, this sounds like something you should keep track of to make sure you have stuff to do when you've blocked time for it! Let's talk about that next.