Where should I put stress in the sentence "How do you do?"?

I am studying intonation and stress in English, and would like advice on where to put stress on these sentences.

1. "How do you do?"
Does it sound like this? HOW do you DO?
2. Where should I put stress on this sentence to get an answer "No, I defenitely not. "
"Did you say you were holding a party?" Should I put it on "Did" or "say"? Or somewhere else?

Thank you so much.