How do I keep some variables in all layouts?

I'm working on a local multiplayer game, so I need that when Gamepad 4 connects as Player 2 the variable Player2 will always equal Gamepad4 (until it disconnects of course).

But I don't know how to keep the variable Player2 from the "Lobby" Layout to the "Game" Layout.

Sorry for my bad English.

Use global variables. They can be accessed from any layout in the project.

Thank you!

Works like I wanted.