Not quite finished with the cutie mark yet, looking for some gem-looking pearls.
The mane and tail was a challenge! but I simply did like I did on Fluttershy and Pinkie, tho the shaping required some more effort in twisting and turning to make it look (more or less) like Rarity's mane. I also had to sew a lot more to make it stay this way. I actually sewed a bit only in the mane to secure the shape, and then fastened it additionally to the body. The tail is simply attached at the top, like on the others, then shaped and fastened with knots and stitches.
Pony pattern by Terri Oda:
[link]