Measure your mattress and estimate its weight. In general, twin mattresses weigh about 60lbs, double mattresses weigh about 90lbs, queen mattresses weigh about 105lbs and king mattresses weigh about 125lbs (mattress foundations and/or box springs weigh between 50-75lbs.)
Visit an online shipping rate comparison website (see Resources). You will be asked to enter the zip code you are shipping the mattress to, the zip code you are shipping the mattress from, and the approximate dimensions and weight of your mattress.
Decide whether or not to insure your mattress. If it is valuable enough to warrant the cost of shipping, the shipping company will recommend insurance.
Pack your mattress in an appropriate mattress carton (memory foam and extra-thick mattresses require special mattress cartons). Mattress cartons are available for purchase online or from any moving company.
Mark the mattress "Lay Flat --- Memory Foam" if it is a memory foam mattress. If a memory foam mattress is stored in an upright position for more than several minutes, the layers will begin to separate.
Arrange for the shipper to pick up your mattress if you cannot transport it to the shipping counter on your own.