You use
Stuffplug NG to do that. The command is /xpsm (in a conversationwindow just like /nick) putting colours in is done the same as putting colour in your nick (ctrl+k), just make sure there's still a space after /xpsm.
If it's your first time installing Stuffplug NG make sure you check the "needed" list too when installing (a screen will come up in wich you can choose to install additional plugins etc...you'll see only stuffplug is checked by default..you need to check the list right under that), follow instructions carefully. By installing this list you make sure everything SPNG needs is on your computer.
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