Another variation on the tabletop stretch from Tulip's video, if you don't have a table, is to lie down with a thick, firm pillow under your hips so you can pike your legs in the air, then scissor one leg forward, one back. It's great if you have a friend to help you with the stretch, but if not you can just breathe into it and let gravity do the work.

If you don't have a pillow and your neck and shoulders can handle it, you can prop hips up with your elbows on the ground and hands on your butt. But that's a pretty extreme position and I don't think I get as much benefit out of it.