One key for me is to have a separate desk. My work machine is in its own corner where only work things can happen. The physical separation makes the habit that, “here is where I work” vs “here is where I live”.
I don't really have space for two separate computer desks. But I enforce the divide with pants: work hours means work pants, the same I'd wear to the office, and after work I "commute home" by changing the pants.
It's a stupid thing but I started doing that at the beginning of the pandemic lockdowns and have kept it up ever since.