85″ divided by 7 = 12.14″
Armed with the width measurement from step 1 and the number you calculated in step 3, cut 8 pieces of your contrasting fabric (4 for each curtain) that are .5″ more than each of those.
For instance, my width measurement was 42″ and my number from step 3 was 12.14″. To calculate the length and width of my stripe pieces, I needed to add .5″ to each of those measurements.
42″ + .5″ = 42.5″
12.14″ + .5″ = 12.64″ (I rounded this number down to .625 [5/8] for simplicity’s sake)
I cut 8 black stripes that were each 42.5″ x 12.625″.
Fold the short edges of your stripe pieces under 1/4″; press. Now, fold under the long edges of the pieces 1/4″ and press again. Set each of the stripe pieces aside for now.
Lay one of your drapery panels face up on a large work surface. (I did this on the floor.) Line the top and side edges of one of your stripe pieces up with the top edge and adjoining side of the drapery panel; pin into place. Edgestitch 1/8″ from the outer edges of this all the way around the outer perimeter of the stripe piece to affix it to the panel.
Helpful hint: When stitching, be sure your bobbin thread color matches the color of your drapery panel so that the stitching isn’t visible from the back of the drapes.
Now, stitch another stripe piece to the bottom edge of the same panel, making sure all of the edges are precisely aligned. You should now have a drapery panel with a stripe along the top and bottom edges.
Using the measurement you calculated in step 3, measure down that distance from the bottom edge of your upper stripe, marking the placement with a washable ink pen. Align the long edge of one of your stripe pieces with these markings. Pin and stitch this stripe as you did the previous stripes in step 6.
Now, measure up from the top edge of the bottom stripe in a similar fashion, marking the placement with your washable pen. Align one of the long edges of one of your stripe pieces with these markings, and pin and stitch this stripe into place.
Refer to the diagram below for how to calculate the stripe placement.
Repeat steps 6 & 7 to complete your remaining drapery panel.
You are finished!