For a two-piece clasp, string on each end: a spacer, a crimp bead, a spacer, Wire Guardian (optional), one half of the clasp. Check the fit, and add or remove beads if necessary. Go back through the beads just strung and tighten the wire. Crimp
the crimp bead and trim the excess wire.
Alternatively, follow these steps to attach a lobster claw clasp on one end and a soldered jump ring or chain extender on the other.