Hey:
I attempted my very first diagonal pleat a few days ago, and the results are in:

Some observations:
1. I don't expect (or attempt) perfection in the pleats, but next time, I think I'll try to keep it a little narrower.
2. I'm learning that one of my favorite color combos is Yellow/Orange/Black, which I call "Candy Corn". Makes sense, as I love Halloween!
3. I should have used more black dye outside the pleats. Despite squeezing the material to spread the dye uniformly, the black parts still came out somewhat uneven.
That said, I'm still 80% happy with the result.
Tie-Dye Todd