[1.8.9] Best way to create a GUI with buttons?

[GalianRyu]

Hey All,

 

So all I want to do is present a user with a simple "Yes/No" option when an Item is used that determines what the item actually does.  I have utilized GuiScreen a lot (for books/tutorials), so making a GUI isn't hard, but I'm curious what the best way is to make the server aware of which button is pressed?

 

Most GUI tutorials literally just say "do something here" and I've looked at packeting tutorials and every different one has you doing different things to create a packet so I'm not sure what's the best/cleanest/least-likely-to-cause-problems way to handle this fairly simple return to the server?

 

Any help is greatly appreciated.