ESSENTIAL TIP: Stand.

Aside from the fact that this is one of my favorite REM songs, it's good counsel for communications. Most of us "walk and talk" when we're talking to a group.  Which means that the collective eyes of the group need to track us as we move about.  For many of us, even an introduction finds us fidgeting, shifting, and shuffling.  Make your audience -- whether 1 or 100 -- do less work: balance your weight equally on both feet, stand straight, give them a nice target.  You will speak with more ease and more confidence, and your audience will find that you are easier to listen to.  Unless there's a reason to "walk and talk," don't.