I’m probably not the best person to come to about writing rituals but I figured I’d give my two-cents. I basically make sure that, when I’m writing, I do it every day. You have to have a set time every day where you can sit down and write without being distracted. The only way to get better at writing is to do it every day. If you need a ritual like starting off with a prompt, then go right ahead and do it!
If you have your own writing ritual please let me know in the comments below and share your experiences!