How can i make a gui pop up and go away with one single keydown?

Hey, How can i do a keyDown function do the same thing only make it reappear and dissapear if you press the same button?

You would use the KeyDown event and check if the GUI is visible. If the GUI is not visible then make it visible vice versa.

Example

mouse.KeyDown:connect(function(k)
if k:lower()=="t" then
gui.Visible=not gui.Visible
end
end)

For this then you will need a KeyDown Event. And you can, like l0cky said, change the visibility of the gui to the opposite of it was when you pressed the key, or you can delete it and make it reappear. I'm going to explain the latter since you already have an example of the Visibility method.

--LocalScript

mouse = game.Players.LocalPlayer:GetMouse() --Get the players mouse
val = 0 --I'll explain later
keyy = "g" --The key to press
gui = PathToGui --Specify the gui to appear / reappear

mouse.KeyDown:connect(function(key) --Keydown event
	if key:lower() == keyy then --Check the key they pressed
		val = val + 1
		if val == 1 then
			g = gui:Clone()
			g.Parent = game.Players.LocalPlayer.PlayerGui
			g.Name = "ClneGui"
		elseif val == 2 then
			game.Players.LocalPlayer.PlayerGui:FindFirstChild("ClneGui"):Destroy()
			val = 0
		end
	end
end)

So what I did here is I made a value, set it to zero, so when they press 'g' the first time, it moves the value to 1, and malkes the gui appear. If it's at 2 then it sets it to 0 and destroys the gui. So it's like a neverending loop.

Hope you're satisfied with this explanation if not tell me I'd be happy to explain further(:

-Goulstem