Here are two similar pieces by Daphne Gray-Grant about how to accomplish more as a writer (Article One, Article Two).
I want to focus on a single suggestion Gray-Grant makes in both, which is to write in whatever few moments you can snatch away from other things you’re doing. You’re dressed and ready to go to the party, but you don’t have to leave for fifteen minutes? Use that time to write. Dinner’s in the oven and the buzzer won’t go off for twenty minutes? Write. Someone’s going to pick you up in ten minutes to go somewhere? Write.