The structure of the bowline is identical to that of the Sheet Bend, except that it is formed at the end of a single line.
1. Form a counter clockwise overhand loop in the standing part. Leave the tail about twice as long as the size of the loop desired.
2. Pass the working end up through the loop from below.
3. Pass the working end around behind the standing part.
4. Pass the working end back down through the loop.
5. Fair the knot by tightening the loop on the standing part while holding the loop.
6. To add security, tie a double overhand knot around the loop to prevent the bowline from untying in slippery line.
Photos and directions courtesy of Columbia what knot