Dust off the exterior of your steamer trunk with a dry cloth, making sure to get inside the crevices around its embellishments.
Mix a solution of one part bleach to nine parts water in a spray bottle. Lightly spray the outside of the trunk and spread the solution with a clean cloth.
Allow the solution to soak in for a few minutes, then wipe off the exterior of the trunk with a clean, damp cloth.
Open the trunk and assess its condition. Antique trunks may have a mildew scent inside from years of storage. If this is the case, remove the lining. Cloth lining may simply be cut out with a sharp knife, while paper lining will likely need to be dampened and scraped out with a 2- to 3-inch scraping tool.
Clean the inside of the trunk using the same combination of bleach solution followed by water with which you cleaned the outside of the trunk.
Leave the trunk open for several days to allow it to completely dry.
Lightly sand the inside of the trunk and wipe it out with a damp cloth.
Apply two coats of oil-based polyurethane with a paintbrush to seal the interior of the trunk. Leave the trunk open until it dries.
Fill the trunk with anything that needs to be stored in your living room, like throw blankets or remote controls. Place it in front of a couch or chair so that you may use it as an ottoman or coffee table.