Silver tips, like many tetras, are not sexually dimporphic. The females tend to be plumper, especially when egg-laden, but there is not a noticable size or coloration difference between genders.
Breeding is similar to danios--they are scatterers. So, have a substrate that will allow eggs to fall through to avoid predation by the adults--small glass marbles work well. Keep a grouping in the tank, condition with good foods. Females will get plump, and courting behavior will occur--shaking and chasing, females shimmying over a spot on the gravel with other fish darting around (males trying to fertilize, other females and some males looking for a quick snack). Remove the adults about 3-4 days after the end of courting behavior, and start watching for tiny wrigglers. Crushed flakes, tiny amounts of crumbled hard boiled egg yolk, infusoria, and fry food will work--make sure the keep the tank clean.
They are not easy to breed, but it can be done.