To use, simply insert the cord's end into the finding until it is almost peaking out the other side.
With chain nose pliers, grip the cord end finding in the middle and ONLY crimp the CENTER area. Squeeze until the center portion of the cord end is flattened and the cord is secure. Also, be sure to postion the cord end so that the finding's loop is HORIZONTAL, not vertical or your finding will break when you crimp down on it. See pictures below.
There you have it! The finished cord end. Repeat for the second side and attach your clasp or beading to the loops. You can easily find these types of crimp-style cord ends at most bead suppliers. ArtBeads.com has a nice selection of these in different sizes and metal finishes.