On my boat I have the large Canadian flag on the stern rail. It has no lower position, so I leavie it alone. I have a smaller Canadian flag that I use on the dinghy on Canada Day. I can fly it from the Starboard spreader, on a halyard that allows a half mast position.
At home I have a flag pole and as I am there now, that flag is at half mast.
I am no monarchist, but fly the flag at half mast out of respect for the Queen, who brought dignity, calm and wisdom to her position, even though no power over her subjects here in Canada. Long live the King.