It’s going to sound completely backwards and dumb, but you just sit down and put fingers to keyboard (pen to paper) and write. Even if you just write “blaaaaaaaaaaah”

You have to force yourself to just do it. I find it helps to visualise it in my head as an actual brickwall, and envision myself taking it down brick by brick. It helps me do chores.

That, or a hard deadline (like an inspection) will scare me into doing the chore regardless of the thickness of the wall.