Vessels travelling UPSTREAM should be prepared to give way to vessels travelling DOWNSTREAM at bridges, in narrows or on bends.
Unless there are signs or buoys saying otherwise keep to the right hand side of the navigable channel but remember there is likely to be shoaling (a build up of silt) on the inside of bends. Never be tempted to cut corners.
The right hand side of the boat facing the bow (front) is Starbaord the left hand side is Port.
Going UPSTREAM: A green (starboard) buoy you leave to your starboard side; a red (port) buoy you leave to your port side. Black buoys and red and white buoys indicate underwater obstructions and can be passed on either side.
IMPORTANT you reverse the way you read buoys when going DOWNSTREAM.
When approaching a vessel travelling in the opposite direction alter course to Starboard, under normal circumstances vessels should always pass each other "Red to Red" or left hand side to left hand side.