Position of your Hands on the Bike:

Avoid numbness in your fingers by moving your the position of your hands often on the bike. Hold solid enough to keep your hands on to the handlebar at unexpected shocks but not so tight that the shock goes up in your arms. For similar safety reasons you should keep your thumbs around the handlebar rather than resting on the top.

Read also the Bike Position article!

Make the bike fit your body. Do not force your body to fit the bike.