I like to put two lines next to the ball number for looks, and then two lines next to the TP5x logo for putting alignment. I like to keep it clean and I use a tool for it. Must be the OCD.
I'm surprised anyone playing in a competetion wouldn't be marking their ball to begin with for that exact reason.
I've been playing custom golf balls that have my initials on them - AH and my high school basketball number 24 as the number on the ball.
In addition, I still put a blue dot next to the logo and a line for putting over the model.
I've been doing it for a few years now. it's a good conversation piece and it's something i find kind of cool anyways.
I color in the logo with a red marker - always red. I also have a putting line along the ball as well.
Keeps it simple, and not too distracting with a bunch of letters, numbers, or dots on the ball. Simple yet effective!