Cyclists should ride predictably and with the flow of traffic. Signal your intentions to motorists and always yield to traffic. Understand basic maintenance. You can learn a lot from local bike advocates, cycling organizations, and from reading. Carry an extra inner tube and a patch kit.
Bike tires are more susceptible to flats than car treads.
Be prepared for the weather. The right kind of clothing will allow you to ride comfortably even on the coldest of days. Padded shorts can bring comfort to the most sensitive, tender part of your core, and when it's happy, you'll be happy. Pearl Izumi makes touring shorts that are comfortable and functional. The cushion will reduce the jarring on the wrists, elbows, shoulders, and neck.