How do I change the Resolution on Rust when the writing is to big?

I’m trying to change my Resolution but I pressed the dont show me this unless the options button isnt on can somebody help me pls.

[editline]29th December 2013[/editline]

and its up close so I cant play it correctly

You need to do that before you log into the game…

I can’t I pressed the don’t show me this, you know the box that you pick your resolution it doesnt show up anymore and by the way I have a mac.