Mentally, what will you tell yourself as a product manager when walking into a room full of board members?
"The audience wants you to succeed". Those are the words my very wise friend shared with me that he learned back in acting school. We often step into a "presentation mode" being ready for a fight. A fight against audience, that is. However, if you empathize with people who have gathered to listen to you, regardless of the context and their status, most of the time they want you to tell them something they will deem "good" - hear a good proposal, learn something new, feel heard if they are offering advice/feedback. It's very hard to deliver that if you're starting from a fight mode. So I love this technique taught to young actors to overcome the fear of stage - remember that the audience's best and desired outcome of an act is not to boo you, but to applaud. They want you to succeed. And so does any audience you will ever have to present to as a product manager.