2. Do all the math before you buy your supplies. Remember that rope is sold by the foot, and that the "recipe" quantity is in yards. I lucked out on this one. I bought approx. 315 feet of rope, and 3+ yards of fabric that was 60 inches wide. I then figured out that the petticoat as described was only 28 inches in diameter. I stood on a tape measure, looked at 28 inches and decided I wanted it wider. It turns out that 3 yards in circumference (108 inches) gives a farthingale that is 34 inches in diameter. Since my fabric was 60 inches wide, I could make the change without having to go out and buy different fabric. I also ended up with too much rope. Each piece needed to be 3 yards long, and the finished farthingale has 14 ridges. That's only 126 feet of rope.
3. If you plan to wash your farthingale, wash your rope. Corollary: Don't choose a rope you can't wash. Just as you should pre-wash fabric before you use it, pre-wash the rope, too. You don't want to find out too late that the rope is going to shrink. I used poplin for the fabric, and deliberately chose a cotton/polyester rope. I threw the rope into the wash (on hot) with the fabric.
Wash rope like you'd wash yarn. Wind the rope into a loose coil just as you would a hose or extension cord. Tie string around it at four points so it can't tangle (as much--believe me, it will find a way despite anything you do). Wash.
4. Don't choose a rope that is going to give you slivers. In the course of making the farthingale, you are going to be handling the rope a lot. Hemp can tear up your fingers.
5. Sew both seams before adding the rope. Once the rope is in place, you won't be able to sew the seam by machine unless you have a heavy duty industrial type machine. I used a soft rope that was 1/8 inch in diameter and had to hand sew the seam.
6. Stagger the rope joins. If you don't, the farthingale will bend inward at the joins. Again, I lucked out on this one. I had left 1/2 inch of rope in the seam allowance at one end (the other I cut flush with the stitching line). I was able to sew this extra down in such a way as to prevent the bend. It wasn't fun, and I don't recommend it.
7. Use a lot of pins, and don't bother to iron the creases. I used indelible ink to mark my ridges. I found that ironing them did nothing to help keep the rope straight. However, pinning the rope in every 2 inches did. The pins ran parallel to the rope, just outside the edge of the zipper foot.
8. Make the first 3 or 4 ridges closer together than the others. I made them all 2 inches apart (before sewing), and then went back and added an extra round between the first two. I ended up with the bottom 3 ridges too close together. They have a tendency to turn under. I should've made the first three 1 1/2 inches apart to begin with, and gradually increased the depth to 2 or 3 inches.
9. If you shape the pieces, you may not need starch. I followed the recipe and gathered the farthingale to the waistbands (after putting 5 pleats in the front so there wouldn't be as many unflattering gathers). The roped bottom curves in gently in about 3 places (it varies). However, if you were to shape the pieces so that no gathering was necessary, and shorten the rope as you went up from the bottom, you might find that for lightweight skirts, the farthingale wouldn't need to be starched. It would be much more transportable unstarched.
10. I used a pretty long stitch length. I found that as I added ridges, the weight and stiffness shortened the stitches. I wouldn't say the machine struggled, but it did make a difference.
11. I quilted the waistbands and put an extra layer of poplin inside. I used 1 inch grosgrain ribbon for the ties, each approx. 1/2 yard long (for a total of 2 yards of ribbon).
12. I only roped the bottom 1/2 yard of the farthingale. It would be interesting to know how it would turn out if you used heavier rope, put the ridges farther apart and took them up closer to the waist.