I decided to buy one in the torishop and I don't know how to use it or how it works. Help?

If you type /em in-game, and then whatever you want to say after that it shows up over your toris' head.

Seeing as how Ititches said that he bought it in the shop, I believe he is referring to the emote colors. When you buy an item named *Insert color* Emote, it then changes the color of all of your emotes (shown above in Gradeger's post) to *Insert color*. You will find this item in your deactivated inventory if you have not already activated it.