In our public speaking course, the issue of what to wear arises regularly. Here are my thoughts.
Dress appropriately for your audience - don't worry about dress changes during the breaks unless you deliver the Oscars. Even that 'extraordinary' event creates negativity in some fields when you consider that many people in this world don't have more than one change of good clothes.
For formal situations, wear a suit. In less formal situations, a smart jacket, shirt, trousers and good shoes. Jeans and trainers will attract criticism from some organisations.I worked in Romania in the summer, and some classes were delivered outside the venue in an outdoor museum. The students were in shorts, and so was I.
I recently went to an event dressed informally, and all of my Executive audience arrived in suits. (The message from the HR person never got through to them). My opening line to them was, 'I do have a suit..' which got a laugh and broke the ice.
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