Flies for bones run from about size six to size one and usually are tied inverted to keep grass off of the point. Both weighted and unweighted versions should be carried. Some should have weedguards, too. Snapping shrimp, bonefish specials, Clouser deep minnows, and various types of epoxy flies are all popular and effective. Most good bonefishermen believe that presentation is much more important than pattern.
Simple techniques work for bonefish and success depends on how effectively they're carried out.
When one is sighted cast in front of it and close enough that the fish can see or hear the fly, but not close enough to spook it. Bonefish move fairly quickly and you can lead them by five or six feet and still be in the ballpark. Take care not to let the fly look like it's attacking the fish. The fly should be presented so that it looks like it's fleeing from its predator. The second technique requires the purchase of ten dozen or so shrimp, and the manufacture of a chumming tube.