To write coloured text you will need to put these codes in before you type anything.

In rs1 only, to write coloured text you write:

Color	How to Make
Random Flashing	@ran@
Red	@red@
Dark Red	@dre@
Orange	@ora@ -or- @lre@
Light Orange	@or1@
Dark Orange	@or2@
Red-Orange	@or3@
Yellow	@yel@
Yellow-Green	@gr1@
Green	@gre@ -or- @gr3@
Light Green	@gr2@
Blue	@blu@
Cyan	@cya@
Magenta	@mag@
Black	@bla@
White	@whi@

and then the text..

For rs2 only ...

Color & Effect Codes
Code	Effect	Other Combos
red:	Red text	»red:wave: »red:scroll
yellow:	Yellow text	»yellow:wave: »yellow:scroll:
green:	Green text	»green:wave: »green:scroll:
cyan:	Bright Blue text	»cyan:wave: »cyan:scroll:
purple:	Purple text	»purple:wave: »purple:scroll:
white:	White text	»white:wave: »white:scroll:
scroll:	Text scrolls right to left.	-
wave:	Text waves up and down.	-
flash1:	Text cycles red to yellow quickly.	»flash1:wave: »flash1:scroll:
flash2:	Text cycles blue to cyan quickly.	»flash2:wave: »flash2:scroll:
flash3:	Text cycles green to light green quickly.	»flash3:wave: »flash3:scroll:
glow1:	Text fades red to blue.	»glow1:wave: »glow1:scroll:
glow2:	Text fades red to purple to blue.	»glow2:wave: »glow2:scroll:
glow3:	Text fades white to green to blue.	»glow3:wave: »glow3:scroll:

Taken from here