Lay flat and use a ball to massage along the line of the base of your skull. When you find a good pressure point, hold steady on it for 30sec. Try to find at least 3 pressure points like that. Can be done on the ground, or in bed for less pressure. If a firm ball is too uncomfortable, try a tennis ball
Place your fingers on outside of mouth and find a ropey/tight spot to release. Spend 30sec per pressure point and aim to find at least 3 of these points.
Place your thumb on the inside of your mouth and your fingers on the outside. Squeeze the pressure point in between your thumb and a finger to release it for 30sec. Aim to find 2-3 spots like this to release
Slouched
Over-correcting
Check that your upper traps are relaxed
Check that your lower back muscles are relaxed