To begin the bracelet, separate one of the wrapping strands from the rest of the bracelet. Simply wrap that strand tightly around the other strands. You can switch colors and wrap with more than one at a time to get different types of stripes. To switch colors, add the former wrapping strand to the filler strands and pick up a new wrapping strand. This is the basic bracelet.
There are several variations I have learned or taught myself. A couple I learned while I was in Ireland a couple years ago and I had one of these done in my hair on Grafton Street in Dublin. It was really neat- there were street vendors all over the place and some girls were doing these for a couple pounds apiece.
The first variation is a spiral on a solid background. It's easy- when switching colors, pull a second wrapping strand out. Wrap with the first strand only but keep the second one outside rather than as a filler. When you have wrapped as far as you want with the first, take the second and spiral it around the wrapped section. Put both in with the fillers when switching colors.
The second variation is a cris-cross. The only difference between it and the spiral is that instead of only taking a second wrapping strand out, take two more out. This means you have to use the filler strand of the same color if you want both parts of the cris-cross to be the same color. Spiral one strand around the wrapped section one way and one the other way.
That's about all I do with wrapped bracelets, but I have started to add beads to the necklaces. Just make sure that the hole is big enough for the necklace to fit through. Oh, that's another thing- these bracelets are very flexible in terms of thickness. Just use more or fewer filler strands.