Now this Quick Change Artists on America's Got Talent is amazing. Wish I knew how they did it, it'd make getting ready for work in the morning so much easier....
You're right man, that's friggin crazy!
I mean seriously, I don't know how they do that.
The trick is simple. Just google "Quick Change Costumes" and you will see that all clothing are simple fastened by hooks, velcro, or pop-up buttons, or "false" seams and you can easily change clothes in seconds. This simple magic trick is old and has been used since 1911.