Tim Flagler of Tightline Productions demonstrates how to make a tapered leader, here a 10-ft 4X tapered leader. This a good leader for a typical trout nymphing rig.
Tapered Leader Formula
The leader formula used is a standard 60/20/20 where the leader consists of 60% butt section, 20% mid-section and 20% tippet.
So for a 10-foot leader we would need a 6-foot long butt section, 2-foot long mid-section, and a 2-foot long tippet section.
Tapered Leader Materials
Butt Section: 4-ft Maxima Chameleon 30-lb + 2-ft Maxima Chameleon 20-lb
Mid Section: 1-ft Maxima Ultragreen 15-lb + 1-ft Maxima Ultragreen 8-lb
Tippet Section: 1-ft Maxima Ultragreen 6-lb + 14-18" Maxima Ultragreen 4-lb
Tim also recommends attaching a tippet ring to the end of the tippet section to make it easier to attach new tippet material and help prolong the life of your hand-tied tapered leader.