Start out by familiarizing yourself with the area and possible routes via maps, both paper and online (Google, Yahoo, Mapquest, etc). Then pick out some routes and drive them, map in hand to explore alternatives. I usually try to drive them during my normal or would-be commuting times, to get a better idea of the traffic volumes and patterns. From there, you should have 1 or more routes picked out that you can ride on a weekend to give you a bicycle perspective.
It's a good idea to know the area like the back of your hand so you can easily adjust your route on the fly to compensate for construction, accidents, weather, etc.
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"Let us hope our weapons are never needed --but do not forget what the common people knew when they demanded the Bill of Rights: An armed citizenry is the first defense, the best defense, and the final defense against tyranny. If guns are outlawed, only the government will have guns. Only the police, the secret police, the military, the hired servants of our rulers. Only the government -- and a few outlaws. I intend to be among the outlaws" - Edward Abbey