I like to dress smart casual, suits are nice but I sweat too much in them so I only wear a suit if it's a special occasion. My shirts are always black cotton esp. if the milonga is at night. I always bring a change of shirt. Trousers are black and I prefer natural fibres but synthetic is OK because it keeps its shape, which is especially good if I'm travelling. I'm more concerned about odor so I spritz with a men's scent (not too much) and always apply deodorant, brush my teeth and gargle before a milonga. In general I don't like wearing shirts made of synthetic fibres and my only experience with the synthetic wicking material made me smell bad. So never again.