How do I make a gui pop up at a stage and then disappear at another stage?

I would really like to know how to do so since I want players to know in my obby that they are close the the end like a final five gui and then at the winner stage the gui disappears but a new gui come up saying you won

This isn't a Hard question. But I'd like to introduce you to the roblox wikia if you haven't already been introduced. The wikia is a very reliable resource for scripting and GUI programming.

http://wiki.roblox.com/index.php/Beginner's_GUI_Tutorial

Contact me any further questions.