You can colour the letters in your name by using ^ followed by a value from 0 to 8, to get black letters in your name use ^9

^1 = Red
^2 = Green
^3 = Yellow
^4 = Blue
^5 = Cyan
^6 = Magenta
^7 = White
^8 = Grey
^9 = Black

seta ui_name "^1C^2o^3l^4o^5u^6r^7s"

Will show your name as:

Colours