Figuring mercerised cotton would be easier to start with than embroidery floss I pulled out some skeins and started knotting, using the tutorials and patterns I found on a site called Friendship-Bracelets.
|My first friendship bracelets ever...|
The only drawback using mercerised cotton could be that it seems to get fuzzy after you've been knotting for a while. Although that might depend on the quality of your cotton: I also made a bracelet using a different kind (one I remember being more expensive) and it stayed smooth from start to finish.
These bracelets have made me want to try and make my own patterns. Now that IS complicated... ;)