The Leader knot makes a strong connection between two lines. If joining a heavy leader to a lighter main line make five or six turns with the lighter line instead of the three turns shown in the diagram.
1) Lay the two lines to be joined parallel to each other, facing in opposite directions. Then lay the end of one line over the other line.
2) Make three wraps around both lines then pass the end back through the loops that you have formed. Pull gently to snug up the knot.
3) Now do the same with the other line and again gently tighten the knot.
4) When both sides of the knot are formed, lubricate them well with saliva and slowly pull on both lines to bring the two knots together. You may need to push the knots with your finger tips to help them to slide easily.
5) Pull the finished knot up tight and trim the tag ends close.