Wash it in hot water and soap. If it can not be washed you have to put it in a plastic garbage bag and not use it for at least 50 days. I would not use it for over 2 months to be safe. You need to vacuum off the mattress and get rid of the bag so it is out of your house or garage then spray down the mattress with a spray that is made for mattresses. You can use Lysol but you wont be able to use that on your furniture. I sprayed the rugs with that mattress spray to but do a test so your make sure it is color safe because I had no problems because mine was light cream. This was a very embarrassing time in my life. My kids got lice when my ex took them on vacation on a house boat and they got it from the beds.
You can't you have to get rid of it they lay eggs there and they will hatch in it
You have to use very hot water and a lot of bleach and that should get rid of them.
Put the sheets on the hottest wash possible and dry outside or in a tumble drier. They can live for weeks in the head but rarely more than 48 hours without food. If it is a mattress I would put it in the garage for three days. Another thing you can do is put the bedding in a large plastic sack and put it in a deep freeze. It might even be prudent to treat all your hair and go and live elsewhere for a few days.