STEP 1: Measure the inside width at 3 locations - the top, middle and bottom. Record the smallest of the 3 measurements. This is your ordering width. We will make the necessary deductions (approx. 3/8" to 1/2").
STEP 2: Measure the height at 3 locations - the left side, middle and right side. Record the largest of the 3 measurements. This is your ordering height.
STEP 1: Measure the width of the area you wish to cover. If space allows we recommend adding 2-3" (1-1 1/2" each side) to this measurement to help eliminate light seepage. This is your ordering width. The factory will make the fabric width of your shade to the width ordered. The headrail width will be 1/4" wider than the width ordered.
STEP 2: Measure the height of the area you wish to cover. This is your ordering height. Be sure to take into account the flat mounting surface (listed above) needed when measuring the area you want to cover with your shade. The factory will make the height of your shade to the height ordered. Generally 3" - 4" added to the height of your opening (including molding or framework you wish to cover) will allow you room to mount above the window frame.