If you own a I-Pod or I-Phone, download one of the climbing knot I-Phone applications from the iTunes store - great for personal use or on-the-job education. Most applications show a step-by-step view of each knot making it easy to see how they are tied.
Treetools also offer the oldschool method - Pro-Knotcards: waterproof, hard-plastic cards riveted together showing a variety of common tree climbing knots. Very handy for your gear bag or glove box - a quickreference when you need them. Pro-Knot cards are far more rugged than the I-Phone but nowhere near as sexy.Thanks to Drew Bristow from DB Tree for this link.