Next to the submit reply button is a button labled "Go Advanced"
If you click that it will place you in the advanced posting options set up, and you will notice a bunch of additional icons. One of those icons should be a large letter A with a line underneath and an arrow next to it indicating that the icon can be clicked open. You can either highlight the text you wish to color and select the color from the menu and it was change it when posted. Alternatively you can simply select the color and the coding will be layed down and all you have to do is type your text inbetween [color] tags.
"Its only a little bit on fire"