Grab your vacuum cleaner's upholstery attachment and go over the entire surface of the mattress, including the sides. Pay special attention to seams and break out the crevice attachment to get any hidden dirt or dust.
4. Spot clean your mattress with a stain remover
Never soak your mattress or apply water or cleaning solution directly to it. Memory foam, for example, isn't supposed to even get wet at all. For that reason, it's important to proceed with caution and operate on the principle that less is more.
That being said, you want to spot clean stains with a stain remover, and the stain remover will depend on the type of stain and the type of mattress. For biological stains, reach for an enzyme cleaner. Spray the cleaner onto a clean white cloth, and then blot the stained area with the cloth. After that, you can apply cold water to a different clean cloth and continue blotting until the stain lifts. The goal here is to use as little product and moisture as possible. This method is ideal for blood, sweat, vomit, urine and other related stains.
As an alternative to an enzyme-based cleaner, you can make your own DIY solution by mixing dish soap with water and apply just the resulting foam to the stain. You can also make a DIY solution of equal parts cold water and hydrogen peroxide.
5. Sprinkle baking soda all over the entire mattress
If you can't put your mattress out in the sun and fresh air, baking soda is the next best thing. Sprinkle a layer over the entire top of the mattress and leave for several hours (or better yet, apply before an overnight trip). Baking soda will break down acid and absorb any remaining moisture or odor. The longer you can leave baking soda on the mattress, the better it will work! As the mattress sits with the baking soda, open any windows in the room to let the light and sunshine in. The sun's UV rays will actually help kill any mold or bacteria on the mattress.
6. Vacuum again
Once the baking soda has worked its magic, thoroughly vacuum it up. (If you have a fabric headboard, now's a good time to vacuum that, as well! Might as well get a fresh start with everything bed-related.)
7. Flip the mattress
Now that side one is spotless, flip the mattress and repeat steps 1-5 so both sides are equally fresh and clean. Flipping, of course, should be done at regular intervals, whether you're deep cleaning the mattress or not. The conventional wisdom has been that people should flip their mattress every three months, but that rule of thumb only applies to spring mattresses because they compress over time. As mattresses get more specialized, your best bet is to check with the model manufacturer. (The foam, for instance, only needs to be rotated 180 degrees every few months, while only the top pad of double sided mattress needs to be flipped and turned.)
(As a general rule of thumb, mattresses should be flipped every three months—or more often if you start to notice any sagging. Consistent mattress flipping will help the mattress wear more evenly and last longer.)
8. Protect the mattress
Now that you know how to clean a mattress, it's time to protect it. Once it's fully dry, cover your fresh mattress with a mattress protector, which will make cleaning easier in the future and protect from spills, dirt, and other unpleasantries (i.e. bed bugs).
9. Keep out dust with a fitted sheet
“Using fitted sheets that are regularly washed, and keeping the area around the mattress clean should protect it from any dust,” says Neil. That said, wrapping mattresses and box springs in mattress encasement's ensures that dust mites don’t take up residence, says Ed—an especially good idea for those who suffer from allergies or asthma.
10. Know when it’s time for an upgrade.
Cleaning a mattress will no doubt extend the life of your mattress and make it a treat to sleep on, but all good things must come to an end. After eight years or so, consider investing in a new mattress. Body impressions and sagging indicate that it’s no longer providing adequate support, says Ed. “It’s also important to listen to your body,” says Neil. “Waking up in pain or sleeping poorly every night are signs that it’s time to move on.”