Did my PPL at a school with a relaxed & friendly atmosphere. Some instructors wore an open shirt or poloshirt which looked just right. Others wore collar & tie daily, smart but a little OTT. The only rule was that instructors had to wear long trousers - understandable, but I did pity them when the temperature passed 40 degC.
All students are different, but my 2p-worth is that if I'm in vacation mode (t-shirt & shorts), I'd prefer not to fly with someone who looks like an extra from Reservoir Dogs. (Would much rather fly with someone else, in her bikini!
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