To deep clean a mattress, follow these key steps:

1. Strip and wash all bedding to remove dirt and germs.
2. Vacuum the mattress thoroughly using an upholstery attachment, focusing on seams and crevices to remove dust and dead skin.
3. Spot-clean any stains with appropriate cleaners, applying the solution sparingly and blotting rather than rubbing.
4. Deodorize by sprinkling baking soda over the surface, letting it sit for several hours, then vacuuming it up.
5. If possible, flip or rotate the mattress and repeat the cleaning process on the other side.
6. Allow the mattress to air dry completely before replacing bedding to prevent moisture buildup.

These practices help remove dust, allergens, stains, and odors, keeping the mattress clean and fresh for better sleep hygiene. Avoid soaking the mattress or using harsh chemicals to protect its integrity.