One of the bonuses in Bioshock Infinite for owning either the Bioshock Collection or the Season Pass is a damage upgrade and golden skins for the pistol and machine gun. We'll show you where to get these perks, and explain about turning them off later.
How to Get the Golden Guns
Bioshock Infinite includes some shiny gold skins for both the pistol and machine gun, as well as a damage upgrade. Both the skins and the upgrade should be included and installed in the guns from the beginning, meaning that you won't need to select them. Some have reported issues with this, but they should've been applied by the time you get through to the restaurant where the Lutece skins give you your first Infusion. If it hasn't happened by then, you may need to start a new game for the skins to trigger.
How to Disable the Golden Gun Skins
Bad news: there is currently no way to disable the golden skins or the damage upgrade on either the machine gun or the pistol, so if you don't like them, you'll have to pick up different kinds of guns you don't have the gold skins for. You can't even drop them and pick up a different machine gun or pistol; the dull metal plating turns to gold the moment Booker touches it. We'll be sure to update this page if a solution or patch is issued, but we wouldn't hold out for it happening: the Bioshock Collection is four years old at time of writing and Bioshock infinite is nearly twice that.
Still, there's other things you can do in Bioshock to take your minds off your inescapable wealth. If you want to know how to solve all the Ciphers and Codes in Bioshock Infinite, just follow this link here. Or if you want to know about the consequences of the Cage/Bird choice, we've got a page on that too.