How do i make an Private Server only gui?

I want only players in a private server to have a ScreenGUI enabled.
I dont know how to do that, so can anybody help?

Try this:

local Players = game:GetService("Players")
-- is this a VIP server?
if game.PrivateServerId ~= "" and game.PrivateServerOwnerId ~= 0 then
    -- listen for new players being added
        -- check if the player is the server owner
        if player.UserId == game.PrivateServerOwnerId then

            -- put here your gui
            game.ServerStorage.VIPGui:Clone().Parent = player.PlayerGui -- set the gui Reset to false