You can draw your own, use a stencil, or even trace a wide font.
Rounded edges work best.
After drawing the border of your letters with a medium-tipped black marker, draw in the outlines of the patches with a very fine tipped marker or pen such as a Sakura Gelly Roll. Finally, color in your patches. We used Milky pens by Pentel for the alphabet and Berol PrismaColor colored pencils for the title.