|Today's super popular knotless tapered leaders are great in most general situations but don't always work for all things. A couple of situations for which I like to create my own leaders are for indicator nymphing and Czech or Polish nymphing.
For all nymph fishing it is important to remember that a thinner diameter leader will allow flies to sink much faster to get in the fish zone sooner and will allow your flies more movement and a more natural drift. Although current types and speeds, as well as depths and fly sizes vary, it is good to go with a leader that tapers quickly, generally within a few feet from the knot to the fly line, to a long length of 2X, 3X, 4X, or even 5X or 6X material.
Choose your tippet diameter according to fly size and weight, current speed, and fish size. Go with the finest material for small flies and a bit larger material for large weighted nymphs and faster water. Choose length according to the depth of the stream. Attach the indicator to the butt section near the start of the finer diameter material.
For Czech and Polish nymphing it is good to include a 4 - 6 inch section of 20 or 30 pound amnesia or other bright monofilament in the butt section for additional help in detecting strikes. Experiment with your own leaders to find what works best on your particular waters and it will result in more fish caught nymphing.