A few years ago, I bought myself a pair of trousers with zips round the thigh, so you could remove the legs to make shorts. These proved ideal for the weather conditions marshalling on the Hebridean Challenge (adventure race the length of Outer Hebrides / Western Isles) - and I also discovered that opening the zip a short distance made insulin injections into thigh very easy! Only the last night ceidhl was more formal - clean T shirts all round and kilts worn by those who had them; I just brought a clan tartan sash to wear over my T shirt, as full female tarten dress / kilt would be a lot to carry.