Chinese knotting is quite an artform in traditional Chinese culture. Although gorgeous, they can be quite complex and time consuming to make too. But here's a tutorial to make a simple, but elegant one that can be used as a little charm for keychains, bags, or whatever.

You'll need some pins, some kind of foam base that can hold up those pins, and some nylon cord available at craft stores in all kinds of colors.

 
Cut about 16" of nylon cord. Pin it to the foam like so.
Use as many pins as you need to keep cord in place.

 
Fold up the bottom tail so that it overlaps the right loop. Pin in place.
Then fold the right loop over the top loop. Pin in place.

 
Fold the top loop over the left loop. Pin in place. Get it now?
Lastly, fold the left loop over the bottom tail, but string it through
the loop made in the first foldover.

 
Remove all pins and carefully pull all the loops and ends out to tighten knot.
Flip the knot over so it looks like the right picture. Place on foam again.

 
Repeat the fold-over steps from earlier all over again, with the bottom tail
and right-top-left loops. Tighten the knot by pulling all the loops again.
You should now have a chinese knot! Add decorative beads if desired by easing
it into the center of the knot. Add a dab of glue to secure in place.

 
Make some knots at the tails of the cord.
You can secure the knot by using a cigarette lighter and very briefly burn
the ends so that they very slightly melt into the knot. (see right picture)

The finished product!