Consider developing and including a MISSION STATEMENT of 25 words or less on the reverse side of your business or personal card. I did this from 1983. It can make a significant impact when shared.
When speaking to an audience be meticulous about acknowledging your sources if using quotes or referring to a particular thesis of thought. Plagiarism may not be intended but can be a speech blot.
Know your AUDIENCE CONTEXT and speak in a genre with which they are familiar and therefore feel comfortable. Talking above the heads of the audience would be unfortunate. Research audience background.