Your credibility will be built on how your audience perceives your competence, your character and your charisma.
Let’s look at that first element of credibility – competence. To be seen as credible you need to be seen as competent.
Obviously you need to know your material, and know it very well. Know it so that you can answer questions that go deep into your subject. Also know your limitations and how you can refer questions to someone who is an expert.
Establish your competence right from the beginning, by ensuring your audience is aware of your credentials and experience. These can be written, very factually into your advertising material, website and brochures. They can also be written into the introduction you are given when you speak. You can also weave them into your speech, and particularly into the introduction. Bragging will not work here. Stories will, however be incredibly effective. Make sure the stories support a point you are making, and it would be good if the point is not necessarily about your competence. Use stories about your experiences, about your client successes and case studies.
Being well organised will show your competence.
Confident presentation will indicate competence. Be prepared for your presentation so that the confidence is genuine. Use eye contact to further establish your confidence and sincerity – your comfort with your subject and the act of sharing your information. Composure – emotional control – is anther facet of this. Be prepared for anything that might throw your emotional control.
Finally, use quotations, statistics and other support material from sources that are held in high regard by your audience. If you are quoting a source on health, for example, you would choose, say, the Mayo Clinic rather than, for example, Wikipedia.
Plant the seeds of your credibility throughout your speech or presentation. Establish your competence, and you will have established a foundation for successfully persuading your audience to act, be or think in the way you wanted.