If in any doubt be smart. Smart hair, shoes and smart well pressed clothes. Don’t fall into the trap of getting up on stage looking casual (you’ll look scruffy). If it’s smart casual, always dress at the smart end of smart casual. If you are a woman always wear your hair up, avoid high heels and wear something with a waistband (to attach your radio microphone). If you are required to sit on a discussion panel, then always wear trousers.