I used the Sienna Dress Pattern by Lil Blue Boo, shortened to t-shirt length. The yellow top of the shirt is appliqued by machine, I added some blue hand embroidery to the border (you can just barely see it on Jessie's shirt, but the stitching is there), and the red swirls and number are flocked Silhouette heat transfer material.
Very Jessie, don't you think? I looked everywhere to find that swirly pattern for my shirt, but came up with nothing. In the end, I just sketched it out myself. After getting the shape right on graph paper, I traced it using a thick black sharpie and scanned the image into my computer. Then I imported the graphic into my Silhouette software and traced the outline to get the perfect cut.
You have no idea how this t-shirt has the wheels in my head turning for Halloween. Thanks to a hilarious suggestion from my husband, Ruby is going to be rocking an awesome costume this year (fingers crossed).