Page 392 - Bob Holtzman "The Field Guide to Knots How to Identify, Tie, and Untie Over 80 Essential Knots for Outdoor Pursuits"

1. Make a bight in one rope. If the two ropes are of different diameters, make the bight in the heavier one.
Pass the working end of the other rope through the bight from back to front, then around the bight, going
first over the working end before coming back to the front over the standing part.

2. Pass the working end of the second rope under itself. The second rope will form an underhand crossing
turn over the bight of the first rope. Make sure both working ends exit the knot on the same side.

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