Posterior neck mobilization
Lying on your back, place a spikey ball or a lacrosse ball behind your head, along the bony ridge of your skull, your occiput.
Starting at the divot in the center of the ridge, roll the ball along the base of your skull to the corner of your ear, and turn your head to the opposite side.
To increase the pressure, place your opposite arm across your forehead.
Roll the ball back and forth, stopping at any extra tender spots to scrub with back-and-forth movements.
2 minutes. Repeat on the other side.