This is a question possibly directed more at those lucky people who live in Italy, Greece, Spain or France (or the South of England?).

From what I can see of those stylish Italians in particular, the open sunroof often appears to be in a deliberate concertina when open. This obscures a bit of the opening but maybe stops it flapping without having to use the special "D" strap.

Anyone got a close-up picture of how they stow it because I have stopped using my sunroof above town speeds as the wind catches it and the metal bar bangs on the roof. I think the replacement vinyl is a much softer and lighter gauge.

Peter i am opening my sunroof like you described ''deliberate concertina''
With one hand on the latch and the other on the metal bar, i am directing the bar at the back so it is stowed under the sunroof frame so i have no bangs when driving. I hope picture helps, the arrow shows where the metal middle bar is stowed.

This is mine. Admittedly I'd want to pull over if doing this from inside the car, as it probably takes more time than a stay at a traffic light. This is pretty much the required level of folding to expose the clip on the roof to fasten it.

Disclaimer - yet to drive at speed with roof open! Hoping to have some parts by next week that mean I can do a proper test of this fold