Originally Posted by LobWedge
If they're fluffy headcovers and they "look" clean, sprinkle baking soda on them, let them sit for a few hours, then take the shop-vac to them to get out the powder. The baking soda will suck up the odour. If it's really strong, you may have to do it twice.
If they're the fake leather/suede ones, get a small to medium sized cardboard box, take a washed out tuna can (or similar shallow container), put about 1" of white vinegar in the container and set it alongside the headcovers in the box. Close the box and let it sit for a couple of days. The vinegar will neutralize the smoke smell.