When I'm having writer's block of the variety where I'm capable of producing words, but they're crap, I simply write the crap. I write the crappiest version of the scene, just to get the ideas out and onto the page, then come back and edit heavily when I am feeling more inspired.

When I'm having writer's block of the variety where I just straight up can't write at all, I try to do some kind of activity where I am using my body, but not my mind - taking a walk, showering, doodling, etc. - with the hopes that my brain will start "writing."

Good luck with whichever variety you're having!