To prevent bed bugs from entering your suitcase, you will need to pre-treat it, with diatomaceous earth. Bed bugs often hitch hike home with you, when you stay over night in hotels or on long trips. They will normally stow away in your suitcase. To prevent that from happening, dust your suitcase with a diatomaceous earth compound. For this, you will need a paintbrush, diatomaceous earth, and a large plastic bag. Sprinkle a little onto your suitcase, use a dry paint brush to spread the diatomaceous earth compound of the zipper and exposed areas of the suitcase. Place your suitcase in a large plastic bag. Store it, in that way, until it is used.