It's easy for a dealer to provide professional looking, sewn-on lettering and numbering, IF he does a few simple things.
1. Start with proven materials - The lettering recommended is polyester twill fabric. It looks as sharp as rayon-cotton twill and does some things that rayon-cotton doesn't. It shrinks less than 1% versus up to 15%... it holds color better... and it won't tear at the stitches. The thread should be 100% cotton, size 00, vat-dyed and mercerized. This thread is strong, durable and color-fast.
2. Zig-zag stitch - Always use a zig-zag stitch.
3. Start at the bottom of the letter or number.
4. Differences in stitching for lettering sizes
* For 6" to 12" numbers or letters use 16 stitches for every inch with a 1/3" wide stitch.
* For 3" and 4" numbers and letters use 20 stitches for every inch, with the stitches being slightly less than an 1/8" wide.
* For 2" numbers and letters use 20 stitches per inch with a 3/32" wide stitch.
5. Corners and other special situations
* For outside corners, stitch to the tip of the corner. Then start the other side of the corner at the tip so that the stitches
* For inside corners, sew 2 stitches past the corner then start the next side so that 2 stitches overlap the first stitching.
* When finishing the number or letter, sew 4 to 8 stitches past the beginning stitches.
* If the bobbin runs out of thread during a job, start the stitches from the new thread 1/4" into the previous stitching.
Follow these tips and your sewn-on lettering will have an excellent appearance and should stay in place for as long as the garment lasts.