Install the bottom and top track to the door opening, using the 2-inch wood screws. Screws for the top track go directly into the upper door frame. The bottom track fastens to the floor sheathing and may require cutting and removing a strip of the carpet, unless installed over tile or laminate flooring.
Measure the distance between the top and bottom tracks with the tape measure, then subtract the amount that the door panels will hang below the rollers in the top track. This figure is the height of the door panels for the sliding closet door.
Measure the width of the door opening with the tape measure. Decide how many sliding door panels will be utilized. Allow a 2- to 3-inch overlap for each overlap point for the doors. For example, if two sliding panels will be used for a closet door with a 50-inch opening, you will need two panels, each 26 inches wide.