Keep in mind how high, low or loud your voice is (volume) and how it rises and falls while you talk (pitch). Projecting doesn’t mean shouting: it means adding energy and life to the voice and body, revealing the humanity and feelings behind the words in ways that create a connection between you and your listeners.
Use volume to draw attention to important sections of your talk, either becoming quieter to draw your listeners in, or becoming louder to emphasise a point.