Place a small, firm foam roller on the floor in a large room. Recline on your back so that your neck is resting comfortably on the foam roller. Keep your arms flat on the ground, and lie with your back and head at rest. If you don’t have a foam roller in your home already, you can purchase one at any store that sells yoga supplies or exercise equipment, or simply use a rolled up towel. Gently push your hips upward until they’re about 2–4 inches (5.1–10.2 cm) high. Lift your rear without changing the position of your neck or head. As you lift up your lower body, start rolling your neck left and right on top of the foam roller. As you keep your hips in the air and turn your head back and forth, you’ll feel the muscles in your neck begin to relax If you need to stabilize your neck, clasp your arms together behind your head as you move over the roller. Keep your back arched and your hips in the air. Push your body forward with your legs so that your neck slides up and down over the roller. Continue to slowly turn your head left and right on the roller, so that all of your neck muscles and vertebrae have a chance to loosen up. Keep rolling until you feel the muscles relax. This should also stop any neck pain you’re experiencing, even if you don’t hear a cracking sound. Try to keep your head and shoulders as relaxed as possible while you’re rolling your neck. This will keep the muscles loose and allow you to fully crack your neck. Stop rolling your neck if you feel any pain. Some people may find that the tension in their neck moves down to their upper back while they’re using the foam roller. If this happens to you, move the foam roller down until it’s under your shoulder blades. Lower your hips and chest until you’re lying flat on the roller. Use your legs to move your body back and forth until your lower back relaxes. This step is optional. If your lower back feels fine after you’ve cracked your neck, you may skip this step.

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Write a summary of the previous text in Indonesian:
Berbaringlah di lantai sambil meletakkan lengkung leher belakang di atas rol stirofoam. Angkat pinggul dan punggung dari lantai agar Anda bertumpu pada leher dan telapak kaki. Bergeraklah maju mundur untuk merilekskan leher yang disangga oleh rol. Pindahkan rol ke punggung jika otot punggung terasa tegang.