- 1). Remove the pillow-top mattress to inspect whether the cause of the sagging is due to the actual mattress or the box spring. A board underneath a mattress in which the "box spring" is featured in the bed, such as day bed frames, can help fix sagging mattress issues -- though if the sagging is due to broken springs within the mattress, it may be time to replace the mattress completely; broken springs in mattresses can occasionally poke through fabric, which can result in injury.
- 2). Flip the pillow-top mattress over to fix sags and help fluff the mattress, if it is a pillow top on both sides of the mattress. Do this about once a month to keep the mattress in shape. If it is not a pillow top on both sides of the mattress, rotate the mattress once a month so the top of the mattress becomes the bottom. Alternate sleeping on different sides of the mattress to avoid uneven wear on your pillow top.
- 3). Place thick comforters or towels between the bed sheet and your pillow-top mattress to fix sags and to help even out the mattress. Lie down on your pillow-top mattress to ensure the comforters or towels are fixed to your liking, and adjust as needed. If possible, use a comforter made up of down feathers, which will have a similar cushy feel to a pillow-top mattress.
- 4). Insert a piece of memory foam between the sheet and the pillow top in the affected area, as an alternative to comforters and towels.
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