Step 1:

• Use a metal measuring tape for accuracy.
• Verify each measurement.
• Because windows are not perfectly square, measuring width measurement both top and bottom and length measurement on both right and left side will avoid surprises after the treatment has been made.
• Measure all windows even if they appear to be identical.

Step 2:

Consider the placement of the window treatment for both form and function.

• Do you want to make a small window appear larger?
• Do you only want to treat the window itself?
• What encumbrances need to be considered, i.e.- metal frames, ceiling mounts, window hardware etc?

Consider all these options before you determine what style you want.