#1 Practice your speech many times
It has been said many times, but that doesn't make it any less valuable. Practicing your speaking does make it more effective and helps build your confidence.
When practicing your speech, do it standing up and make sure you time it as you go. If you are using powerpoints or handouts ensure that you include them in your practice too.
For a simple 30 minute seminar you will need to spend approximately 3-4 hours of practice and refinement to the material to get it right. More time if you are new to the topic material.
#2 Be ready with the answers
From what I have heard from students learning how to deliver training courses in the VET sector, is that a large part of their lack of confidence comes from worrying that the people listening to them know more about the topic than the speaker does.
When practicing your speaking look for questions that might be raised from your points and make a note of the answer needed. If you don't know the answer, now is the time to find out.
The key tip here is to remind yourself that you aren't required to know everything about the subject and someone in the audience will know something you don't. However this is not a problem because;
Most people feel your pain and wont attack you because they wouldn't like it done to them.
The type of person that knows what you don't, is also the type of person to act professionally and not point out your lack of knowledge in the area of your speech.
Even if they think they know the answer, drawing attention to themselves by pointing it out during the seminar creates a risk they could be wrong and seen as impolite or worse.
With this just remind yourself that you have been asked to the presentation of speaking engagement and they weren't. You had the courage to stand up in public and give it a go, they didn't.
#3 Use your nervous energy
Have a drink of water before you start to help with that dry mouth and get rid of all your noisy objects on your person. Anything that makes a sound will be heightened when you get nervous and start playing with them.
You will have butterflies as they say, but it is just your nervous energy flooding your body with adrenalin to run away or fight. Take this energy and use it to build attention and interest in the seminar right from the start. It will only take a minute for this nervous energy to fade away leaving you talking normally and not like a hypo rabbit.
#4 Slow your talking speed down
This energy will make everything you say come out a 100-words a minute in a confused jumble. Remind yourself to speak slower and avoid any large or any unfamiliar words at the beginning to avoid stumbling over them while you are nervous.
#5 Give yourself some breathing room
To help get over the initial stage fright from public speaking a good idea is to let the audience members speak while you are getting comfortable up there. Ask them a question of two to get them engaged and listening.
Does anyone have questions before we start?
I am going to speak about X, does anyone have any experience with this that we can use in the activities later?
Or the good fallback, poke fun at yourself and make a joke, and let the tension flow out of the seminar when the audience laughs. A laugh is a good way to reduce the nervous energy and tension felt when you first get on the public stage.