Visiting Your Bridge
To visit your bridge while in Sector Space or docked at a space port, click the arrow icon near your minimap (as indicated by the red circle in the image above) and in the list of options you will find "Visit Your Bridge". Here, you can invite friends or leave your character idle while you go take your first shower in a few days because you've been too busy fighting Klingons to bother.
Any Bridge Officers you may have will be present on your bridge at their relevant stations.
In order to leave your bridge (or a friend's bridge), you can use the "Beam up" option. You can also leave the bridge by standing near the Captain's chair, which brings up the option "Return to tactical view", or by interacting with the glowing turbolift door that can be found in the starboard alcove at the rear of the bridge.