The pattern is written for 42 stitches. If you cast on 84, you won't get what's in the picture, especially with the short rows.
Your gauge should be 17 stitches per 4 inches, so if you're using a thin yarn, you might want to double it.
The short rows should be read as written. If it says to knit to the 6th MT, and then back to the 5th MT, then that's what you do. Doing the short rows is what will give you the ruffles.
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog
IngridKH on Ravelry