Q) How do I use this?
A) Go into Mod Settings, and to the Per-Player tab. There's a text box to type your color into under "My Player Color". If you want to try out colors quickly, you can use the new /mycolor command!

Q) How could I possibly choose any color using just words?
A) With 3 words or less, you can choose from over 890 colors. Use up to 4 words and you can make more than 8,890 colors! Tones are essentially Hue/Saturation/Lightness operations, allowing you to make very specific color adjustments.

Q) There are other mods out there that let you choose a player color. You just click a color. Why make this?
A) Color pickers and stuff are fairly trivial to implement (especially if you've made them before). I feel that translating words into a color is a far more interesting problem than translating coordinates-someone-clicked into a color. This approach is new, and was much more fun to solve!