The mod I am working on uses a key press event - this works fine on single-player but I am trying to make it work in multiplayer. Currently the key handler is registered in the main mod class preInit() using FMLCommonHandler.instance().bus().register(new KeyHandler()). I know that I need to register it in the client proxy instead, but I do not know how to do that - I've looked for tutorials on this but so far what I've found either isn't updated for 1.7.10 or doesn't show the code. I reckon the solution to this is quite simple, but I want to be sure of what I'm doing. Thanks.

Solution: Move the registration to a method in your ClientProxy, and call that method from your main class:

@Mod.EventHandler
public void load(FMLInitializationEvent event) {
proxy.registerHandlers(); // server proxy does nothing; client proxy registers key handler
}

That's what I thought. Just making sure. Thanks.