Remove all detachable items like lights, bags and quick release parts.
Lock to a bike rack, parking meter or firmly affixed sign pole - these are the most secure places but must be in accordance with State laws regarding the securing of a bicycle.
See images to the below for locking depictions.
Always lock your bike, even if you're just leaving it for a moment, or it can literally "roll away."
Always lock through the frame and a wheel. Add a cable or second U-lock to lock the second wheel. See the diagram above.
Always use a modern, high quality U-lock. U-locks are strong and better ones come with theft warranties. Buy the most expensive lock you can afford. Only buy a U-lock with a flat or disc key. Cylindrical keyed locks are more easily picked. See the diagram above.
Always lock to something secure like a bike rack, parking meter or firmly affixed sign pole.
Beware of locking to "sucker poles" that are loosely bolted down and can easily be removed.
Remove detachable items like lights, bags and quick release parts from your bike and take them with you.
Consider replacing quick release parts with ones that bolt on for greater security.
Lock your bike close by and keep it in view as much as possible.
Lock near entrances and well-lit, secure areas.
Lock your bike inside if space is available.
Lock your bike when keeping it in a garage or other unattended indoor area, even if you can only lock the bike to itself by locking the frame to a wheel.
Check out the lock manufacturer's warranty and product replacement policy.
Taking the time to lock up your bike with a high quality, relatively inexpensive U-lock is the best way to keep your bike yours. It's better to lock your bike than to buy a new one!