Every fisherman should be able to tie the simple, strong knot, the best for attaching lures to your line.
The Albright knot is used to connect two lines that differ greatly in diameter (say, adding a heavy shock leader to light spinning line). This version includes a lock option to keep the knot from coming undone.
A dropper line above your fly, lure, or bait is the perfect way to rig split shot. When you snag, the weight will pull free and you'll keep your terminal tackle.
classic strategy, borrowed from devious salesmen, pays handsome dividends on the water