As promised, here's the photo tutorial for making twisted falls with synthetic knitting yarn. I apologize for my clothing in the tutorial; I was still in my pajamas. But hey, everyone likes sheep-print flannel pants, right? If there's anything unclear in the tutorial or something confusing, please let me know and I'll fix it. I tried to simplify the directions from the text-only ones I posted a few days ago, so hopefully this will make more sense.
1. First, lay the cut end against your crown and find the point on the yarn where either A) your hair ends or B) how long you want the fall to be.
2. Put a twist tie around the yarn at this point (or tie a little thread or some other noticable dividing line). Measure out four lengths equal to the yarn you've marked off, and cut at the end. You'll end up with one very long piece of yarn, with four equal parts on one side of the twist-tie (the long end), and one equal part on the other side of the twist tie (the short end). There's a red circle drawn around the twist tie to make it easy to spot in the picture.
3. Place the cut end of the long tail against the twist-tie and run the yarn through your fingers until it's in a loop. Find the midpoint (where my finger is in the photo). Hold the cut end and the twist tie in your hand and put the midpoint over your toe (or something else to hold it).
4. Stretch it to its full length, keeping the cut end and yarn just below the twist tie in your fingers.
5. Keeping the yarn taut, start twisting it in one direction, over and over until the whole length looks twisted.
6. Once it's evenly twisted, grab the midpoint between your fingers and your toe with the fingers of your other hand. (The piece that you see dangling from my top hand is the short end of the yarn; don't worry about that piece.)
7. Keeping the midpoint taut with your other hand, bring the top down to your toes.
8. Keeping your fingers tight on the end, release the midpoint. You will end up with something that looks like the picture below - a kind of twisted mess.
9. Keeping your fingers tight on the end, smooth the yarn with your other hand, starting at your toe and moving in the direction of the arrow.
10. You will end up with either one of these two pictures. If it looks like the one on the left, with little holes between the yarn (look inside the red circles) then it is too loose. Stretch it out again and continue twisting, then repeat steps 6-9. If your picture looks like the one on the right, smooth and tight without any gaps, then it's fine.
11. Where you've been holding with your fingers, you'll have three different things: a cut end of yarn (1), the piece of the yarn with the twist tie (2), and a loop (3). If you want to have a loop at the top, then move their positions until it looks like the picture on the right, and tie 1 and 2 together around the loop in a firm double-knot. If you don't want a loop at the top, then tie the cut end and the loop together in a firm double-knot around the piece of yarn with the twist-tie.
12. You'll end up with something that looks like this. Snip the loose piece (with the arrow pointing to it) and remove the twist-tie (the other arrow).
13. Lay the twist over your head so the single strand is laying where you're going to braid it into a braid, and the twisted part is hanging the other way (to keep it out of your way while you braid).
14. Braid it into your hair, using it as one strand of the three-strand braid, and using two pieces of your natural hair as the other two strands.
15. You'll end up with something like this: one twist-fall and one braid. Secure braided part with a hair elastic, or if you're lazy like me, just use the end of the yarn to tie it off. Sorry I don't have a picture with a full head of twist-braid falls in place; I don't have an assistant and I'm kept busy keeping an eye on my very active toddler, so it takes me several days of intermittent work to get a full head of falls in place.
Additional instructions if you're just making twist-falls without the piece to be inserted into braids:
1. To make a single twist-fall, follow all steps exactly, except you don't need to have the short end of the yarn; you'll just be working with four equal parts rather than four equal parts plus one equal part, and of course you won't need the twist tie. Hold both cut ends in your hand when twisting. When finishing it off, tie it so the loop is left at the top.
2. To make a double twist-fall, follow all steps exactly, except that you'll have four equal parts, twist tie, and then four more equal parts. Once you've twisted and tied off the yarn on one side of the twist tie, repeat the process to the second half of the yarn; you'll end up with a double twist-fall with both parts tied/secured in the center.
The picture below shows a large single twist-fall (made with 12 strands of yarn), a medium double twist-fall (made with eight strands), and a small double twist-fall (made with four strands).
A picture of me wearing two different sets of twist-falls, braided in two bunches on either side of my head and then tied on top in a loose knot: