Once you've arrived at your destination, you circle the parking lot or city block looking for a place to park. You're probably stressed and not eager to start work. Travelling in twos will make you more visible than travelling solo. If you must bike alone, travel less congested streets. You may travel a few extra miles, but the point is to enjoy your ride.
Most people know the importance of wearing a helmet, being visible, and obeying the traffic laws.
To do so, you must be properly positioned and predictable. Ride in that part of the roadway where motorists expect to see traffic. Ride with traffic, rather than against it. Motorists pulling out from side streets don't expect vehicles to approach from against the flow. Ride in the traffic lane instead of hugging the curb.