Some of the points above may seem obvious but they are easily forgotten. You don't want to give your audience any excuse not to like you and stop listening. The following are just a few of the ways in which you can upset your audience.
PUNCTUALITY, or lack of it, can cause resentment. Your trainees find themselves sitting in a room at 9.00 am and you don't turn up until 9.10. You can just imagine the conversation that might go on behind your back!
DRESS. The way you dress can make the difference between the audience having confidence in you and ignoring you. I don't mean that you need to wear a shirt and tie, (although that's what I was taught), but you should look neat and presentable: it gives you a psychological advantage if you are dressed smarter than your audience.
DEPORTMENT. The generaL way you "carry" yourself can promote confidence in you as a speaker. Look and sound confident, be courteous, say please and thank you when requesting trainees to do something. As a general rule, avoid swearing.
AUDIENCE COMFORT. I used to conduct training courses at customer's premises and I reckon I've come across every type of training facility in more than thirty years. Some are brilliant and give a lovely relaxed atmosphere but far too many places provide facilities I wouldn't send my dog into. If your trainees are not comfortable they won't be listening to you!