Be Easy. Be Nice. Be Professional
You are Your Brand. As a speaker, no matter how much you earn, how big your expertise or how very important you are, you should be a person who is easy to work with.
I know, a lot of speakers say they are easy to work with.
But the reality is often different:
Some speakers lose control when something does not work - like for example they prepared a slide show and it does not work for any reason. Or when they were rescheduled and are not happy with the time or the order of speakers.
As a speaker, you should be flexible and always solution-oriented. Become a part the team even if you are only a guest-speaker.
Mistakes happen wherever people are at work - sometimes due to technical problems, due to some bad preparation or just due to mistakes.
When you are on stage, you are in the focus of your audience. Losing control, screaming or bitching around will ruin your brand, potentially everything you built over years.
Even if a presentation is not perfect in your eyes, don't take it personally and don't take yourself too seriously.
Put your Ego out of the way - or even better: Get rid of it!