When I discovered that you could use freezer paper as a stencil... oh man it was like the heavens opened and a chorus of angels sang.
I cut the "J" out with my awesome KNK-Groove. Best thing on the planet that Groove is. Not going to lie though. There is a learning curve on that think. After you cut out your stencil you iron the paper shiny side down on your fabric.
Then you paint it in. I use the Tulip Soft Matte fabric paint. It's awesome. Seriously. Don't forget to put cardboard in the shirt so the paint doesn't bleed from the front to the back. I also use a stiffer brush when painting on fabric. It just goes on easier.
Let it dry, remove the paper and then lightly iron over it to set it. A perfect personalized gift! And so easy!