I live in Queens and commute over the Queensboro bridge. In Queens, I take the back roads and take a lane. If there's a bike lane, I ride on the tape right at the edge of the bike lane.

Going over the bridge it's pretty intuitive.

In Manhattan, I weave in and out of traffic when it's slow or stopped. When the traffic is flowing I pretty much take a lane. I'll sit in the first third of the lane and I usually turn my head all the way around to make eye contact with the car behind me.