I learned how to make these bracelets when I got the spool in a kit when I was ten or so. Once you get the rhythm down, you can easily complete one of these bracelets in half an hour or less. If you make them really long, then you can make a really cool choker neclace. If you don't have a spool (which you probably don't) then there are several ways to make them.
You will need:
~ Thin elastic cord, which you can find in a Jo-Ann Fabric Store, Michael's, ect. I personally prefer the shinier ones.
~ Beads that fit over the elastic cord. I am using size 6/0 (it says on the package).
~ The smallest crochet hook you can get; mine is 1/2.75mm.
~ A spool. If you don't have one, they are easy to make. All you really need to have is three prongs equally spaced with a hole in the center (that is where the bracelet comes out as you knit it). There are several ways to make a spool. You can take a piece of wood with a coin-sized hole in it and three tacks surrounding it. You could use cardboard and paperclips. You can pretty much use anything, just try to imitate the spool in the picture. I will show you how to make one with an empty tape dispenser, tape, and some wire.
Step 1: Making a Homemade Spool
Take a piece of wire and bend it in half to be about the same width as a small paperclip. Tape it to the inside of the tape dispenser and bend the wire around the back so it stays in place. Make sure that it's super secure because the elastic will pull the wires forward. The wood and tack method is probably better, but I am assuming that more people will have these supplies.
Step 2: Set Up the Spool
First, thread a ton of beads onto the elastic. Don't cut the elastic yet, because you don't know how much you will need. Then make a slip knot and place it on one of the prongs of the spool. My spool has a little arrow next to the first prong that you put the slip knot over. If you made a spool, pick a point and mark it so you know where the slip knot is. This will be important later. To make a slip knot, take the elastic and cross it over about three inches from the end. Then take the long part of the elastic (not the end, the part that is with the rest of the elastic, see the picture) and pull it through the loop you made. Slip that loop over the marked prong. Then following the pictures, loop the elastic around the spool. After you do the first pattern of looping around, you won't have to do it like that again for the rest of the bracelet. You just have to wind the elastic around the outside.
Step 3: Knitting Time!
Take the lower elastic on the prong (there should be two loops, one from the original base and one from looping around the outside) and pull it over the prong using the crochet hook. Keep going around the spool, bringing the elastic around and knitting as you go. When you want to put on beads, just push one of the beads up to the prongs. When you are about to pull a loop over a prong, make sure you pull it over the bead as well. The little arrow or marker on your loom that I told you was important will help you keep track of how many rounds of beads you have done. I like to alternate a round of knitting with a round of beads.
Step 4: Finishing the Bracelet
When you have decided that your bracelet is long enough, take the loop on the first prong and put it on the second prong. Pull the bottom loop over the top one, and repeat on the remaining prongs until there is one left, which you will take with the crochet hook. Cut the elastic so there is an inch or so left. Pull it through the loop and tie a knot with it really tightly. You can just tie the ends together friendship bracelet style or tie on a clasp.
Step 5: Make Some More
Now that you have made one, make some more! They look really great together. You can switch up the number of stitches, charms and and the beads to get some more variety. Have fun!