You need your basic ingredients and for my falls I always use a base of Point 5 wool by Colinette. Midnight (black, or as close as dammit) is the colour. I'm also using some lime green roving. The other yarn pictured here didn't get used in the end. It didn't look right. You'll also need a pair of scissors, two strong elasticated covered hairbands, a needle and thread and some hair beads and other things for decoration if decoration is what you want.
The lime green roving is shown here in the first stages of being formed into dreads. You pull a section of the roving away from the long thick strand you get, and then start rolling it between your hands. All the way along its length. To get a close texture to the fibres keep doing this over and over.
I start by taking strands of Point 5 and counting along the strand a regular number of thicker sections. The wool is both thick and thin and is consistent in this thick/thin texture along its length. So I start with 6 strands, all 7 thick sections long.
Take each strand and take a loop through the hairband - at all stages of this process try not to have the ends of the yarn exactly in line with one another, you get a better look and overall texture to the falls.
Now start to add layers. Don't just keep looping yarn around the band. That way you get a lot of yarn on your band, but there's no bulk to it, the strands will all be spread along the entire band.
What I do is take another 6 strands of Colinette, this time 6 thicknesses long. And I loop them through some of the tighter loops created by the first base layer. Here's a pic of black yarn looped through the roving.
Continue, loop strand after strand through previous loops, so that the strands sit on top of one another. Keep taking a look at your yarn fall. Does it need more stands? Add them. I add two more pieces of roving either side of the first one.
The next layer is made up of 6 strands of Colinette, all 4 thicknesses long, plus more roving.
Once I'm happy with the thickness of the falls I take my needle and thread and sew through all of the loops up at the hairband. Not lots and lots of stitching, just enough to make sure that everything is going to stay in place and be secure.
To complete your falls you can add beads, bells, wound sections of thread, shells, bits of jewellery...anything you can think of.