I’ve gotten several inquiry for this pattern. Thank you for your interest but unfortunately, I didn’t write it all down as I was knitting it. It was another one of my “wing it” project.

I used the following pattern stitch and knitted following the shape and length of an existing sleeveless t-shirt of mine.

The wavy effect at the bottom will appear naturally as you commence further up with the pattern stitch. No extra work to make that effect ;)

As for the ruffles, PU from midway of sleeve edge and worked in stockinette stitch. I YO after every K stitch.

Pattern Stitch:
Multiple of 9 sts + 3

Foundation Row (WS): Purl.
Commence Pattern
1ST ROW:
k1, k2tog, K3, yo twice, k3, #k3tog, k3, yo twice, k3; rep from # to last 3 sts, k2tog, k1.

2ND ROW:
p6, k1, #p8, k1; rep from # to last 5 sts, p5.