Use the chart below for color codes!

§0 Black §1 Dark Blue §2 Dark Green §3 Dark Aqua
§4 Dark Red §5 Dark Purple §6 Gold §7 Gray
§8 Dark Gray §9 Blue §a Green §b Aqua
§c Red §d Light Purple §e Yellow §f White
§k
§l
Bold
§m
Strike
§n
Underline
§o
Italics
§r
Reset

Main Command. Copy and paste this command into commandblock:

Just Menu (for adding on to existing GUI). Copy and paste at the end of the 2nd line:

Click Events (for adding on to existing GUI). Copy and paste at the end of the 3rd line: