Scrape out any remaining liner with a paint scraper. If it is lined with old paper, spraying it first with a water bottle full of half-vinegar and half-water will help soften any old glue remaining.
Fill in any gaps in the trunk with a thin piece of fabric. Cut the fabric to the specific length and width of the gap, gluing it down and allowing it to dry completely.
Measure the inside dimensions of the trunk for each of the surfaces that you plan to line with fabric. You’ll use these measurements to cut a corresponding piece of poster board. You should have measurements for the bottom, both ends, both sides and the top if you plan to line that as well.
Cut the poster board according to the measurements for each surface. Now cut and glue the fabric onto each piece of poster board.
Spray the inside surface with spray contact glue and place the fabric-covered piece of poster board inside, with the fabric facing up. Do this with every piece of poster board covered with fabric. Allow the glue to dry completely.
Fill your trunk with treasures, memorabilia, blankets, toys or other items.