Bowline on the Bight

1. First double the rope to create a "bight" in the rope (an open loop). Then create a small loop in the bight (the doubled rope) just like you would for a basic Bowline, and bring the end of the bight through the small loop. This creates two big loops which hang below the knot.
2. Now open up the end of the bight a little bit and bring it back down over the two main loops, and then continue bringing the end of the bight around behind the two main loops and up to the other side of the small initial loop.
3. Dress and set the knot.

Double Figure-Eight Loop

1. Start with a "slipped" Figure-Eight Loop, which creates two loops where there would normally have been only one loop.
2. Then you slightly open up the end of the "bight", the doubled rope, and pass it all the way around the two main loops and over the knot.
3. Dress and set the knot

Double Alpine Butterfly

1. To tie this knot, first you begin tying the normal Alpine Butterfly.
2. Then you push two bights through.
3. The two bights that you pushed through the loop will become the two main loops of this double-loop knot.
4. Dress the knot before continuing in order to change the sizes of the loops fairly easily.
5. Take the bight (the doubled rope) which is hanging down at the bottom and bring it up and over the two main loops.
6. Finally bring that bight all the way around until it lays on top of the dressed knot, and then finish dressing the knot.