Give the trunk the once over before you begin your project. Although you likely inspected the trunk when you purchased it, areas that need extra work sometimes come to light once you get the trunk home. This step will give you a mental game plan of what you need to do during the upholstery process.
Measure the trunk on all sides, then add at least an inch to all sides to account for the hem in the material so that it doesn't fray once you tack it onto the trunk.
Remove the handle using a screwdriver if necessary. Keep all the pieces since the handle will be reattached to the trunk later.
Mark the material according to your measurements, then cut the material. Use fabric chalk to avoid a permanent mark. Also, mark the inside of the material that will be next to the trunk instead of the side facing the outside. Use a ruler to ensure you have straight edges, which will make the trunk look neater once you put the upholstery on it.
Fold a hem on one side of the material, making sure it's about 1-inch thick and facing down. Tack that edge onto the corresponding side of the trunk. You may have to place upholstery tacks at both corners of the side you're tacking down. Don't put the tacks in the very corner, however; leave about an inch on the ends because you will be folding hems all the way around the material.
Hem each side and tack the corners down. Make sure the material is pulled taught and the hems face the trunk rather than being upward and exposed.
Add upholstery tacks to secure the sides of this piece of material down. These should resemble rivets in the way that they cover the length of the material on each side and spaced about 2 inches apart.
Repeat the process until all the sides of the trunk are covered.
Add corner caps to each corner of the trunk to provide extra reinforcement to the upholstery.
Replace the handle and any other hardware you took off to upholster the trunk.