Choose the type of mattress topper you want for your bed. Memory foam and latex are considered the most comfortable, but they're also the most expensive. A simple eggshell mattress provides extra softness at a fraction of the price. Wool and feather mattress toppers are also available if you have an allergy to synthetic material.
Remove the sheets from your mattress and lay the mattress topper on top. Place it evenly in the center of your mattress so the sides of the topper match the sides of your mattress.
Place the sheets over the mattress and the mattress topper. You may have to buy sheets larger to accommodate the mattress topper.