Flat Cap

A regular reader of this column writes, 'my girlfriend and I haven't done it yet, though we are both keen to try. She is worried about fitting the cap especially with it being a bit frayed at the edges. We would have preferred a new cap but this was all that they had, and the assistant assured us that if it was a bit big, it would shrink to fit, and that this particular product was durable and showerproof but perhaps better left off in a high wind. Can you give us any advice as to the circumstances when we would be safe to use the cap as we are both hoping to pass ourselves as a mature couple of a sensible outlook?'