How can I refresh the lettering on a polished, granite headstone?

[ThursdayTomorrow]

The black lettering on my relatives headstone has come out in many places meaning the words aren’t very visible. I would like to repaint/refresh the lettering.
YouTube seems to have many different ways which makes me nervous as I don’t know which ones actually work - I would hate to leave a terrible mess.
I was thinking enamel paint like you use for little model planes and scraping off the excess.
Has anyone refreshed the lettering on a grave? How did you do it?

Iirc we paid a stonemason.

When we placed my DFs ashes in his parent’s grave, we had the stonemason clean the headstone, repaint the engraving and then add his name. If it’s important enough to you for it to be done, then Id get it done professionally.

Yes, by a stonemason. This isn't a DIY job. IMHO

Assuming it's polished (shiny) granite, you just paint in the letters roughly with a good quality paint (like Japanese lacquer), let it dry, then take off the excess by rubbing with a cuttlefish "bone", which you can buy from pet shops. The cuttlefish is coarse enough to erase the paint, but soft enough not to scratch the granite. It's an easy job.

Thank you. I did think about getting a professional but it’s pretty pricey (on my wages anyway). I definitely take the point about not messing it up though, I wondered if anyone had actually done it themselves but it seems it’s not a common thing to do.
I have seen the cuttlefish method on YouTube, maybe I will try it on just one letter. It is very shiny, polished granite.

@ThursdayTomorrow It really is easy. Remember to let the paint fully dry and you can't go wrong.

I did refresh the lettering on my dad's headstone (why I bothered I don't know, as he was a real shit). Took me a while with a high quality brush and good paint. I had lots of practice after doing a calligraphy course.

When my mum died I had the headstone re-done to add her name and refreshed the whole headstone. Was £1300 by a local stonemason.