How do I make it so if a key is pressed, it does something,then if it's pressed again, it undos it?

When someone presses z, they go into a giant form. I want to make it so if someone presses z again, they return to their original form. This is my code so far. I put Player.Character.Humanoid.BodyDepthScale.Value = Player.Character.Humanoid.BodyDepthScale.Value + 1 Player.Character.Humanoid.BodyHeightScale.Value = Player.Character.Humanoid.BodyHeightScale.Value + 1 Player.Character.Humanoid.BodyWidthScale.Value = Player.Character.Humanoid.BodyWidthScale.Value + 1 Player.Character.Humanoid.HeadScale.Value = Player.Character.Humanoid.HeadScale.Value + 1 a bunch of times because I want a smooth transition while they grow into a giant form.

local Player = game.Players.LocalPlayer
local char = Player.Character
local mouse = Player:GetMouse()
local cooldown = 0
local Humanoid = game.Players.LocalPlayer:FindFirstChild("Humanoid")
mouse.KeyDown:connect(function(k)
	k = k:lower()
	if k == "z" and cooldown == 0 then
		cooldown = 1
		Player.Character.Humanoid.BodyDepthScale.Value = Player.Character.Humanoid.BodyDepthScale.Value + 1
		Player.Character.Humanoid.BodyHeightScale.Value = Player.Character.Humanoid.BodyHeightScale.Value + 1
		Player.Character.Humanoid.BodyWidthScale.Value = Player.Character.Humanoid.BodyWidthScale.Value + 1
		Player.Character.Humanoid.HeadScale.Value = Player.Character.Humanoid.HeadScale.Value + 1
		wait()
		Player.Character.Humanoid.BodyDepthScale.Value = Player.Character.Humanoid.BodyDepthScale.Value + 1
		Player.Character.Humanoid.BodyHeightScale.Value = Player.Character.Humanoid.BodyHeightScale.Value + 1
		Player.Character.Humanoid.BodyWidthScale.Value = Player.Character.Humanoid.BodyWidthScale.Value + 1
		Player.Character.Humanoid.HeadScale.Value = Player.Character.Humanoid.HeadScale.Value + 1
		wait()
		Player.Character.Humanoid.BodyDepthScale.Value = Player.Character.Humanoid.BodyDepthScale.Value + 1
		Player.Character.Humanoid.BodyHeightScale.Value = Player.Character.Humanoid.BodyHeightScale.Value + 1
		Player.Character.Humanoid.BodyWidthScale.Value = Player.Character.Humanoid.BodyWidthScale.Value + 1
		Player.Character.Humanoid.HeadScale.Value = Player.Character.Humanoid.HeadScale.Value + 1
		wait()
		Player.Character.Humanoid.BodyDepthScale.Value = Player.Character.Humanoid.BodyDepthScale.Value + 1
		Player.Character.Humanoid.BodyHeightScale.Value = Player.Character.Humanoid.BodyHeightScale.Value + 1
		Player.Character.Humanoid.BodyWidthScale.Value = Player.Character.Humanoid.BodyWidthScale.Value + 1
		Player.Character.Humanoid.HeadScale.Value = Player.Character.Humanoid.HeadScale.Value + 1
	end
end)