I used fabric paint (NOT the puffy bottles) and a stencil brush. I put a piece of cardboard inside the bag to keep any paint from bleeding through. Better safe than sorry!
I centered the vinyl on the bag and pressed it down as best I could.
Then I stenciled the paint on.
I removed the vinyl while it was still wet.
It bled through under some cracks, but that's ok. Adds character, and it's just for me. ;)
I let it dry completely. Actually, I let it dry overnight because I needed to go out and buy the turquoise paint. I cut a J out and stenciled it on the same way.