And I usually say something like, "I totally get that."
But, getting confident is not a technique, it is really a healing process of which greater confidence is a result.
You can be a confident extrovert, introvert, or like me, a confident ambivert. Confidence operates on a different plane of existence from that of being talkative, or the life of the party.
Think about why people fear public speaking. As someone who attended my leadership talk at Joyner Library pointed out, it's the fear of being judged that gets us.
Logically, you know that you can't please everyone all the time. And really, you don't even want to do that. Remembering that truth in your heart takes practice.