There are lots of cues for improving posture: keep your chest up, pull your stomach in, sit up straight, etc. But my favorite has long been to imagine a string attached to the top of your head pulling you up. (Just keep those abs tight!) Well, imagine no longer!
With an assist from Sensei Hutch (who is clearly envious of my fashion sense, as he should be--look at those pants!), I demonstrate how this works with the real thing. Kids, don't try this at home!
-gary