When the time comes to store your carpets, get them upside down and leave them that way for about a week. Doing that will help get rid of all the dust and dirt that is concentrated in the root of the pile. Dirt in the root of the pile can be dangerous when walking on the carpet, as it nibbles the hair which gets cut with time. After doing that put it back upright and vacuum it. Place it in a nilon or fabric bag and if you choose to use a camphor you will have to wrap it in fabric or paper in order to prevent discoloration. Carpets must be wrapped tight and always be stored horizontally, otherwise when you unwrap them next year there will be waves in their shape.