Should flip or turn the mattress. And switch on the couch - at least one time every three months to maintain the stability of the mattress. And not to one side or the permanent collapse.
Should be flipped or upside down and switch on the bed head-end at least once every 3 months to maintain the stability of the bed and did not give either side a permanent rupture.
You should turn it upside down or back to the bed, and lay down the switch on the head-end for at least 1 times every 3 months, to maintain the security of the bed, and not to one side permanently collapse.