Knowing how to tie a useful knot is a skill that doesn't get much attention outside of sailing and rock climbing, but although I do neither of those things, I like learning new knots. They come in handy in the garden, the kitchen, and any time I have to move something on or in a vehicle.
If you'd like to learn to be more handy with rope and string, I suggest this website, where you can learn new knots. You can easily go step by step, reverse, or even re-orient the knot to see how it looks from another angle. It's called "Animated Knots." They even have neckties!