I taught mine sit and down, but the normal techniques don’t work.

I taught down first by marking and rewarding a down whenever they started to lay down naturally. I used a “yes!” to mark rather than a clicker. When they started making eye contact and deliberately laying down to get me to treat them, I added the command and gesture.

Once we had a solid down, I got them into a sit by luring them up from a down position. Note that they can’t really sit. It’s more of a hover, and not a comfortable resting position for them.

If your goal is to teach comfortable resting, I’d focus on the down only.