When lying down in bed:

Find the mattress that is right for you. While a firm mattress is generally recommended, some people find that softer mattresses reduce their back pain. Your individual comfort should guide your choice.
Choose the right pillow, too. Special pillows are available to help with postural problems resulting from poor sleeping positions. I prefer an organic latex contoured-shape pillow to support the neck.
Avoid sleeping on your stomach.
Sleep on your side or back, which is often helpful for back pain. If you sleep on your side, place a pillow between your legs. If you sleep on your back, keep a pillow under your knees.

Sweet dreams and I hope this helps!