Have someone help you compare the distance between your temples to the distance between the bridge of your nose and your lower lip. Early detection is crucial.
If your third toe is longer than your second, you are probably mad.
Your eyebrows should be no thicker than 20% of their length; if they are thicker than that, you may require corrective surgery.
When you step on the scale, the number you see should make you feel inadequate. If it does not, you are abnormal.
Seeing spots before your eyes is often a sign that you need to redecorate.
If the fingernails on one of your hands are noticeably longer than those on the other, you are probably a classical guitarist, and should purchase an expensive Spanish guitar immediately.
Ask your doctor to calculate your Body Mass Index, and then use variations of that number to play the lottery.
You will never really know whether your head is normally shaped until you shave it bald.