Sterling Silver Toggle Clasps (bar & loop clasps) are popular for bracelet designs, because they're easier to manipulate with one hand than many other clasp styles.
Tips to make sure your jewelry is wearable:
The last few beads you put near the clasp should be small, to make sure the bar will go all the way through the ring (making the clasp easier to close).
When using toggle clasps for bracelets, the bracelet must fit the customer fairly well. If the bracelet is too loose, a short toggle bar might wiggle itself out of its loop. Longer bars can help solve the problem, but won't eliminate it.
To size your bracelets to your customers' wrists, try using a few chain links at the end, between the clasp and the last beads. Then you can remove or add links at the time of sale. Or if you really have a good thing going, make 6.5", 7", and 8" versions of your best-selling styles of bracelets.