How to I create a Screen Gui that switches between morphs?

I'm trying to create a screen gui so that at enter and respawn, you have an option to choose between one of the two sides. Then once you press it, it gives you another screen gui, giving you a list of options to choose between one of the morphs that are given to each respected side. Something similar to this game except without all those other options: http://www.roblox.com/Experimenting-2-place?id=69861153 This is what I currently have:

local p = script.Parent.Parent.Parent.Parent
wait (1)
p.TeamColor = BrickColor.new("INSERTCOLORHERE")

local c = game.Workspace:getCharacterFromPlayer(p)
c:BreakJoints()