Uncle Mortimer, the crazy doctor with a PhD in "Funology", and the creator of the Thrillville amusement parks, is quite the character. Now, with this simple article, you can easily dress like good ole' Uncle Mortimer.
Steps
Get a paisley button-up shirt. It can literally be of any color, as long as they clash (though green is preferred).
Wear a pair of tan or brown cargo pants.
Wear a yellow necktie, and let it hang loosely.
Wear a white lab coat. Don't button/zip it up.
Wear a pair of random shoes. They can range from sandals to boots.
Wear a pair of goggles over your head.
Tips
You can wear a crazy white wig, or dye your hair white with a non-permanent dye.
Wear a pair of plastic gloves, just to add some character to your cosplay.