Help: How to creat a MOD?

Learn C++, learn teeworlds code, then compile it. There's not a complete guide since you have to know that two important things.

If you want to know how to bind messages
press F1 and type

bind <key> say "<text>"

for multiple commands in one bind add a ';' and type the second coammand e.g.

bind <key> say "<text>";+fire

If you press the key you will say the text and shoot at the same time.

To unbind keys type

unbind <key>

I know you've asked how to make a mod but I somehow doubt that you know what you are talking about and regarding your example I would say youre asking for binds and not mods.

Edit: Dune is absolutely right.
I'm sorry.