Slide the curtains onto the curtain rod. Hold the rod with the curtains on it above the window to help determine the hanging height. Have someone else hold the rod for you, if possible, so you will be able to see the curtains at various heights.
Slide the curtain rod out as far as you want it to extend beyond the edges of the window. Slide it far enough so it at least covers the trim around the window. Extend it farther if you want to make the window look wider.
Hold the curtain rod bracket up to the wall underneath the rod to determine where it needs to go to hold the rod in the position you chose. This works best if someone else holds the curtain rod for you.
Draw light marks on the wall to mark the screw holes on the curtain rod bracket. Lower the curtain rod and bracket. Measure the distance from the top of the window frame to the screw hole marks on the bracket. Measure the distance across from the edge of the window frame to the marks. These measurements help you place the screw holes for the bracket at the other end to ensure they are evenly placed.
Measure over and up from the other corner of the window frame to determine the second bracket's location. Hold the bracket at that location and lightly mark the screw holes on the wall.
Hold a level against the wall lined up between the screw holes at either end to determine if they are level. Adjust the marks as necessary to ensure the curtain rod is installed level.
Position the drill so the bit is on top of the first screw hole mark. Drill into the wall slowly to make the starter hole for the screw. Repeat the drilling process on the remaining screw holes to prepare the wall for mounting the curtain rod brackets.