1) If you're a back sleeper: Put a pillow under your knees to allow your spine to maintain its natural curve.
2) If you're a stomach sleeper: Put a pillow under your lower abdomen and pelvis to ease back strain.
3) If you're a side sleeper: Draw your legs up slightly toward your chest and sleep with a pillow (a full body pillow can be comfortable) between your knees.
The Right Mattress and Pillow for Sleep
When it comes to selecting a mattress and pillow, Experts say personal preference and comfort rule. Some people prefer the firmness of a harder mattress, while others are more comfortable on a soft mattress. Experts suggest spending a night in a hotel that offers options for guests to purchase pillows and mattresses so that you can try before you buy. Or, see if your mattress store lets you try out a bed overnight or even longer. If that is not an option, perhaps sleeping on the floor in a sleeping bag may mimic a firm surface, and sleeping on a couch may mimic a softer surface.
Some people may find it helpful to use a contoured pillow to alleviate neck strain or to sleep on just one pillow instead of a stack of several pillows.