To be honest, I don't know why I did this.. only because it is a very simple solution, I guess? I already have my own method of organizing my keys and I never mix my keys up, but since I saw this on pinterest, and it's as simple as taking out a bottle of nail polish and painting my keys.. I went ahead and did it anyway.
This would be super and a bit of a money saver if you like to buy those rubber key labelers. Especially if, like me, you already have a whole lot of nail polish around anyway!
EDIT: It just occurred to me.. I can now change the colours whenever I feel like it! One point for nail polish remover!