Install the valances first so that you can judge how high to place the sheer curtains. Position one of the curtain rod hanging supports parallel with the side of the window frame, at the upper outside edge of the window frame, 1/2 inch from each edge.
Hammer a 1-inch wood nail into the holes on both sides of the curtain rod hanging support. Use a level to properly position the second curtain rod hanging support on the frame on the other side of the window. Secure the second support with two more 1-inch wood nails.
Slide the valance over the curtain rod. Hang the curtain rod on the curtain rod support hardware by holding the rod at an upward angle, inserting the ends over the hardware and lowering the rod to a horizontal position.
Slide both panels of the sheer curtains onto the second curtain rod. Hold the rod up to the window and determine how high you want to hang the shears. Mark the top of the curtain rod where you will install the hardware, 1/2 inch from the outer edge of the window frame. Install the curtain rod support hardware. Check for level before installing the second support. Hang the sheer curtain rod on the hardware.