My technique only:

- If I am jump seating I go up and introduce myself

- If I am non revving I go up and introduce myself

- If I am deadheading I go up and introduce myself

See a pattern here? What I'm getting at is, if I were the Captain I would greatly appreciate knowing who and where all available crew members are on board in the unlikely case we could use their help. It's happened plenty before.

Not to mention, putting a face to a name is always a pleasant way to do it. You meet some interesting folks that you may have only interacted with online. It's a win-win.