We have a fairly 'pat' intro routine. It's not set in stone, but it follows along certain lines. Usually, it's Buddy Holly's 'It Doesn't Matter any More'. I kick it off on a four-chord trick pattern singing a doo-wop harmony over top (we're playing for seniors, remember), the missus does some intro patter over the top introducing us, then a quick change-up and we're into the song proper.

It's a nice structured intro and sets up the audience nicely.