I have a pretty outta-the-box marketing startup idea and a local (very successful) marketing exec has been nice enough to set up a meeting to discuss my idea and offer feedback/advice.

I want to cover my bases with a very basic NDA (nondisclosure) but don't want to come across as amateurish, paranoid or...for lack of a better word ungrateful.

Any tips for the least blank-stare-inducing way to do this?

Thanks.