Aha! another practical question of the sort that HubPages loves!
I turn my mattress every 6 months (January and June) and turn it according to the manufacturer's directions. (head to foot)
At that time, I use a light spray of Febreze to help keep the mattress fresh, but I also use an impermeable mattress protector/cover to keep out moisture and mold and bedbugs? Don't know if it really will keep out a bedbug, but I don't seem to have any, so maybe it works.
If you cannot manage to turn the mattress yourself, It may be possible to turn the whole bed if it is on rollers.
Flipping the mattress is beyond my ability. I would have to hire a maid service.