That short you starred in at film school ten years ago? You don’t look like that any more. Ditch it. The scene you did that was hilarious even though you’re an extra in the background? Ditch it. Show off your best performances that are recent and represent who you are as an actor now, and be ruthless – this is where having someone else edit your reel is so important. They won’t have an emotional attachment to your scenes, they’ll cut away the excess, the boring moments, and leave you with something vibrant and exciting.