You want to wear a jersey today but not the advertisement for a team or brand in the lettering. Or you want to preserve the lettering of a jersey, but not on that jersey. In either case, the process for removing the vinyl letters is the same, and within half an hour the lettering from any jersey will be off the shirt without damaging it or the letters. You won't have to buy any special tailoring equipment or even see a tailor. This process is cheap, easy, and quick.
Clean the jersey. Read the instructions on the label for cleaning. Most jerseys with vinyl lettering should be washed in warm water with like colouring, without bleach, and tumble dried. Do not dry clean.
Spread the jersey out on your ironing board. Heat the lettering you intend to remove with a blow dryer. Don't heat the area too much or you may damage the fabric of the jersey.
Slide a razor blade below a heated section of the lettering to gently pry it away from the shirt. Do this carefully because the razor can cut the jersey. If you're worried about damaging the shirt, use tweezers or another prying tool rather than the blade. Pull the lettering off the jersey enough to finish the job with your fingers.
Press some rubbing alcohol into a cotton ball and smear the ball against any adhesive that was on the area of the jersey below the removed lettering. Let this alcohol soak for about a minute. The adhesive will become moist and flaky. Clean the adhesive off with a rag.
Wash the jersey again as the label instructed before you wear it.
If the letters leave an unpleasant outline on the jersey, apply more heat with the blow dryer. If this doesn't work, use a heat press.
Be careful not to overheat the jersey with the blow dryer, since this can damage the fabric.