Form a loop in the string by grabbing the tag end and doubling it back on the main string. Pinch the loop at the tag end and hold it in place until the knot is tied.
Continue pinching the tag end to the main string and grab the loop with your free hand. Treat the loop as a single piece of string and tie it into an overhand knot.
Wrap the loop through the knot opening one additional time and pull on the loop to tighten the knot. Place the loop on a stable hook or rod and pull on the main line to completely tighten the knot. Cut away the tag end for a smooth connection.
Grab the tag end of the string and cross it over the main line to form a loop. Leave six inches of excess on the tag end to tie the knot.
Pinch the loop at the point where the two section of strings cross. Grab the tag end with your opposite hand and loosely wrap the tag end around the loop to form a second loop.
Slide the tag end between the two loops and pull it between the pinching fingers to hold it in place. Reach through the initial loop and grab the second loop. Pull the second loop through the initial loop until the knot is tight. Clip away the tag end.