Tense release (or TR) is a progressive relaxation technique which helps you relax and release stress and tension. The basic principle is to feel the difference between the tensed and relaxed state and this will help you relax.
TR is especially helpful if you have trouble falling asleep and it can help you get relaxed in just a few minutes. It can also help with headaches and muscle pain.
Lay flat on your back in bed, legs uncrossed. Start by focusing on your breathing. Inhale through your nose and exhale through your mouth. Breathe slowly, take your time.
Tense a muscle and focus on the tensed state and then relax it and focus how it feels when you let go. Keep the tension for 5-10 seconds and then relax for 10 seconds before you repeat. It might take a few repetitions to get your muscle to a fully relaxed state.
Start by focusing on your feet and work your way throughout your body; feet > calves > thighs > butt > abs > back & shoulders > hands & forearms > upper arms > neck > face. When you reach your face, imagine you have just eaten a really sour lemon and squeeze you face together.
You can also practise TR from a seated position.