I am going to tell you how to clean your mattress.
So you know you can't throw your mattress in the washing machine but you can freshen it up and spot clean your mattress without water.
About every six months we flip our mattress. When you do this you can take the time to clean it and freshen your mattress too.
First, strip every thing and wash all your bedding and mattress pad and bed skirt if you have one. While you have the mattress up for flipping vacuum that box spring.
Second, if you have any stains you can use a solution of one part dish soap to two parts hydrogen peroxide. Do not soak any stains but dab a very warm damp clean cloth into the solution and work the stain and keep dabbing it dry with a clean dry cloth. Most mattress stains are protein in nature so this solution to clean the mattress should work. The sooner you get to that stain the better.
Third, when you are done with any spot cleaning of your mattress, let's deodorize it. Take some baking soda and use a sifter or a shaker to sprinkle a thin layer of baking soda over the top of your mattress. Let it sit for at least an hour and then come in with you upholstery attachment and vacuum. Get in between the flap on the side of the pillow top and vacuum all the crevices well.
I am telling you this really does freshen your mattress. I swear it even smells better in your room after a thorough cleaning of your bed.
Now bring in your freshly washed bedding and make up your bed and you will sleep like a baby not only from all that work, but because your bed is so fresh and clean.