The Double Grinner Knot
The Double Grinner Knot is an effective way to join two pieces of similar diameter line together and is particularly effective for joining braid to mono. Make sure that you use at least 5 turns (7 for braid) on each side to ensure that the knot works effectively.
Take your two line ends and line them up parallel to one another with a 6 inch overlap.
Make a loop with one end of line as shown and pass the free end around the other line and through the loop at least 5 times (7 if using braid).
Wet and draw the knot tight.
Repeat with the other end of line.
Moisten and draw the knots together by pulling on the two main lines.