You might not think it matters much what you wear when giving a talk, as long as it is decent and not too scruffy but there are some things worth thinking about when choosing what you wear.
You might like to think of yourself as a bit of a character and reflect this in your fashion sense but remember that you should be presenting the subject, not yourself and all your idiosyncrasies. Wear the sort of clothes that you are comfortable in and that will show some of your character, but not anything that will detract from your talk. All your effort in preparation could be wasted by a simple thing such as a garish dress, jacket, wacky tie or dazzling piece of jewellery that becomes the centre of attention and will be what the audience remembers.
Another important thing to check before you leave your home is that you have not got any tears, holes or seams coming undone anywhere on your clothing. It might seem silly to mention this but I can remember when the only thing spoken about over tea – when the speaker was not in earshot – was the gaping hole in his trousers.
As I said before, if you know you will be using a clip-on mike or, even if you do not know but think it possible, wear something suitable and strong enough to clip it onto. Silky fabrics are slippery and tend to fold over under the weight.
A round-neck top for ladies or men that does not come too close to the neck, but leaves a gap where the mike can sit comfortably; a jacket with a firm lapel; crew-neck jumpers are okay but not if the neckline sits just below the collar of a shirt or blouse and near a tie because scraping of the mike against fabric can occur, with the results I have described.
Think about the fabric of the clothing you have chosen. Is it going to be a nuisance? Ladies, in particular, need to ensure that they do not have any fashionable but trailing scarves, cardigans or long, unruly hair that can get entangled or caught on furniture, flip-charts, mikes, easels or anything else that might be around them.
Be colourful but not garish and distracting, be sensible and sensitive with your clothing. If speaking to a religious group, be considerate to their customs and do not wear a pigskin coat to speak to a group that will not touch pork or wear any animal skin or fur to a group of vegetarians. Other specific groups have different taboos. Research your audience, if necessary. These days you really could find yourself in court if you do not.
It sounds more like a minefield with each of my posts but, once you have thought about these things, sensible preparations are more likely to occur to you when you actually go to face your audiences. Use common sense and you should be all right. I would not want to put anyone speaking in public!