|Bowline, Double sheet bend
|joining two ropes of different diameters
To tie the sheet bend, take the larger rope in one hand. Make a loop in this rope about three inches long and hold both ends of the loop in one hand. Next, take the smaller rope and thread it up the loop. Then wrap the smaller rope around the loop of the larger one going first round the short end. Then tuck it underneath where the smaller rope comes up through the larger rope's loop. Finally, pull the free end of the smaller rope tight to secure the knot.
Make sure the two free ends are on the same side of the knot; otherwise you get a left-handed sheet bend - a knot of significantly reduced strength.
The weaver's knot is a different approach to tie a sheet bend.
If the two ropes to be tied are of very different diameters, the double sheet bend holds better.