Apologies on the late update and crappy photos, my camera hasn't been working (stuck using my old one for now).
Be it for nostalgia or just for fun, I wear a patch vest pretty often. All of my patches are hand-made using one of my two methods. For the first method I take black canvas fabric, draw a general idea with whiteout pens, add detail with clear acrylic, and use black sharpie paint-pens to clean up any mistakes. Finally, I add a few coats of matte, clear acrylic spray paint. Method two is a little more detailed and better for the more complex patches (Nylithia, Dethklok, etc).
Method two involves Canvas Paper, Clear Matte Acrylic Spray, Ultra-Fine Micron Pens, Sharpie Paint Pens, Acrylic Paint, an inkjet printer, and other various tools. First, cut some canvas paper as long as you want, but only 8.5 inches wide (unless your printer can print wider). Then start a PSD, with a width of 8" and a length .5" less than the sheet. Add the logos you want to the PSD with proper spacing. Tell it to print at the bottom of the sheet; feeding thick canvas paper can cause issues, it's best to have more room for error at the start of the sheet. Also, be sure to print on the softer, absorbent side of the paper; the back is typically glossy. Let the printed sheet absorb/dry for 15min, then take it outside and apply a coat of clear acrylic spray. After this dries, you can start filling in the black details with your pens, and larger areas with paint. I use different balances of pen and paint for different patches. Let the paint dry, and then coat with a few more layers of clear acrylic spray.
Above is my favorite patch. The amazing artist Lara Hilgemann drew this for me (freehand in about 2 minutes).
As an apology for nearly missing my (self-appointed) deadline on this post, here are some doodles: