Before you ship your motorcycle you'll be asked to fold back mirrors or other protruding equipment prior to motorcycle shipping. However, in most cases you will not have to drain your gas tank or remove the battery.
Give the bike a good cleaning before it is shipped, and take photographs so you can document its condition before shipment.
Be sure your shipping company knows about any mechanical problems with the bike. Especially, notify them about any leaks that could damage other vehicles in the truck. If they know a bike is leaky, drivers will stow it in the bottom of the carrier to prevent such damage.