Agreed, there is a lot of sports psychology related stuff written about how sportsmen use nervousness to motivate themselves. How do you not show you are nervous ? Because that is not a good signal is it ? I get nervous for interviews I've prepared decently well for. I don't get nervous when I'm either fully prepared or not prepared at all.
As a former gymnast and YC founder, I have some experience with nerves. The best advice is to prepare as hard as you can, and then relax, knowing that you've already done everything you can to succeed.
Obviously, practicing being put on the spot is also valuable - find ways to do things where you have to deliver even while nervous.
