Locate the studs on both closet walls intended for the closet rod with a stud finder. Mark their position with a pencil.
Measure the width between the closet walls using a tape measure. Mark the distance on the closet rod subtracting 1/2 inch to compensate for approximately 1/4-inch-thick rod brackets.
Place the closet rod into a miter box. Line the distance mark up with the 90-degree cross-cut slots on the box. Secure it in place with a clamp. Place the blade of the miter saw into the slots above the rod to make the cut.
Determine the desired height for the closet rod and mark the position on both walls using the measuring tape and pencil.
Mark a line across each wall at the chosen closet rod height. The line must intersect with the marks made to indicate the stud positions. These should be 18 to 24 inches from the back wall of the closet to allow for hanger clearance.
Center one of the closet rod support brackets on the intersecting marked lines on either side of the closet. Mark the bracket screw hole locations with the pencil.
Drill pilot holes into the stud at the marked screw hole positions. Use a drill fitted with the appropriate size wood-boring bit relative to the size screw being used.
Secure the bracket to the wall with wood screws. Tighten clockwise with a screwdriver.
Repeat Steps 6, 7 and 8 on the opposite wall.
Install the closet rod into each of the two brackets. Place the rod ends into the open slots of the brackets and ensure the ends are fully seated.