[podperson]

Speaking as someone who did a lot of competitive public speaking back in the day, the frisson of "panic" just before you start is your friend. I'm worried if I don't feel it.

As for the rest of the advice, it's probably good advice on how not to royally suck, but not on how to actually be great. That said, your competition will probably not be that good. (The fact that Steve Jobs's keynotes are/were held in such high regard is due in some part to how lousy the competition is).

What works for me (and I have no idea if it will work for you) is to write out the entire speech, practice it a couple of times (making corrections as required), then reduce it to points, and speak from the points. That way you are, in a sense, winging it, but you aren't tempted to read the entire thing and you have -- somewhere in the back of your brain -- a strong articulation of the points you want to make.

I don't think any great speech you can think of ("I have a dream", "ask not what you can do for your country", "we shall fight them on the beaches") was "winged" and Steve Jobs famously rehearsed like crazy (as did his hero, Edwin Land).

The fact Jobs's performances came off as pretty natural was no accident. It's one thing to "embrace your ums" if you're a tiny startup, and another if any tiny thing you say will be analyzed by pundits for the next ten years. (Consider how few misstatements Steve Jobs made in all his enormously publicized "keynotes" -- and interviews for that matter.)

[corin_]

"Speaking as someone who did a lot of competitive public speaking back in the day, the frisson of "panic" just before you start is your friend. I'm worried if I don't feel it."

My background is singing professionally (in the past) rather than speaking, but it's fairly similar for the sake of this point.

I agree with the adrenaline being your friend, but disagree that not feeling it is a bad sign. I always found that the amount of adrenaline/panic correlated mostly with the importance of the performance, and a little to do with what the performance was. When it came it was a friend to embrace not ignore, when it didn't it just meant (for me) that it was an easier gig, and I could do as good a job without any emotions boiling up.

[tikhonj]

Rehearsing probably helps for speeches, but I think other sorts of public speaking don't need it as much. Particularly, I am not very likely to deliver a speech; I am much more likely to give a talk or presentation on some subject. Given that I know the subject well, I find improvising the exact wording--not the content or structure--is best for me.

That said, giving a talk about something you know well to a group of people naturally interested in that subject is probably much easier than giving a speech (as long as you know what you're talking about, of course!).