Rule #1: Have a goal.
It helps if this goal is within parameters that you know you can perform within.
Rule #2: Try to meet said goal.
I'm going to assume that you set the goal as a reasonable and thinking adult, so if you're working 9-5 and then coaching football practice four evenings a week, then your goal is based on squeezing in time where you can and that is what YOU CHOSE TO DO. Maybe you chose to wait until the sport season is over. Maybe not. The "trying" part here is all on you.
Rule #3: Don't sweat it if you don't.
A.) Things happen. Elderly parents get sick. Dogs make messes. Kids sign you up for conferences and you forgot. You can handle this. (** You should NOT freak the hell out and scream at everyone about how they are messing up your goal.) Deal with what needs dealt with. Go back to writing when you can. Unless you are under contract for a deadline, IT'S OKAY.
B.) Things don't happen. Sometimes the words aren't there. There are plenty of tricks to getting that rolling again. I'm sure we've spend a week discussing that at some time or another. But where goals are concerned -- and let me reiterate, I'm talking about non-contract, non-deadline, just self-set goals here -- you have to remember writing is an ART. Go for a walk. Do the housework. Rake some leaves. Let that worry shit go; the writing will come back.
The Bottom Line
When I give my time, knowing up front what the expectations are helps me ensure I meet those expectations. That is a very good thing. BUT. When I'm writing, I know what to do, when, where, for how long. I've spent years learning the way to this destination and I don't need to track my progress via word counts, nor do I need that almighty tracking number to hold myself accountable. I'm getting there, or I'm not. If I am, yay! If I'm not, I need to fix something so I do. Period. That is what works for me. Again, writing is ART. You need to be progressing, and if you're not, figure out what works for YOU to keep you progressing. It will be trial and error until you find it, but when you do, it will be your unique way.
May you find it promptly and be abundant.