Measure
the width
Measure the width of the window using a tape measure.
Lay
the fabric down and measure
Lay the fabric face down. Measure a section that is two and a half times the width of the window, plus two inches for seam allowance.
Marking your measurements with chalk, before
cutting your fabric, will keep your valance accurately sized.
Measure
the length
Measure how long you want the valance to be. Double that measurement, add 3 inches for seam allowance, and cut the fabric.
Measure
a hem
Measure a 1-inch hem on both sides of the valance, pin the fabric, and then sew it in place, removing the pins as you sew.
Fold
in half
Fold the valance in half lengthwise, right sides facing out.
The fold should be at the bottom of the valance.
Measure
and sew a one-inch hem
Measure a 1-inch hem from the top of the valance, pin, and sew in place, removing the pins as you sew.
Measure
and stitch
Measure 2 inches below the stitched hem line you just sewed, and mark it with chalk. Sew along the chalk line, creating a pocket for a curtain rod.