Something I use to help me get the most out of my writing time is a YouTube channel that features immersive writing session music. You do a 25-minute sprint, non-stop writing, then you take a 5-minute break. I love listening to music and ambient sounds while I write. It's nice that they have it all on their YouTube videos. A bell goes off after 25 minutes, then again after a 5-minute break. I find I can go longer than 25 minutes, but if I don't take those short breaks, my brain fatigues and I can't write for more than an hour before I need to stop entirely.
What tools help you maintain focus?