Sleeping on a soft bed or couch can strain neck and back muscles since the three curves of the spine are not adequately supported. Sleeping on your stomach is not recommended since it can cause additional strain on the neck and back. Make sure you have a firm mattress that keeps the spine aligned and supports the spinal curvatures. The best sleeping positions are on your back or side. A pillow can be placed under the knees when lying on your back to take pressure off of the lower back.
Sleeping on your side
If you find sleeping on your side comfortable, the best way to ensure maximum comfort is to bend your legs slightly and to have a pillow between your legs, or even a full length body pillow. This position can help keep your skips level and reduce any pain you might have there.
Sleeping on your back
Sleeping on your back can be very good if you have lower back pain. The best position to be in is to put a pillow under your knees to remove the strain from your lower back.
Sleeping on your stomach
It is generally not good for your back to sleep on your stomach, but if you need to for some specific reason, then it will help reduce back strain if you put a pillow under your pelvis and abdomen. As well, using a pillow in this position will also cause strain on your neck, so try sleeping without a pillow, or with a very small one.