A 'head bob' while sitting up in bed without a pillow or blanket can signal readiness for sleep.

“If you can't stand next to your bed, if that's a little too silly for you, sit and sit up on your bed. Don't not like just a little propped up. Your head's not on a pillow. You're not under a blanket. Sit up. Again, you're not going to lose touch of your body's signals. And and worst case scenario, at least you get the head bob. The headbob is is is your friend. The headbob means it's your body telling you you're ready.”