Pulling cuts together with needles and string. But it works well. On the other hand, it doesn't have to be painful. A variety of pain relief options are available, and many emergency departments are using them. Hopefully these options will become more useful in the future once some problems are worked out.
Glues require accurate cut alignment, and are difficult or impossible to adjust once applied.
Sometimes they cause discolored scars. For now, the best treatment for cuts and scrapes is prompt cleaning, and prompt evaluation if the injury is deep, may involve tendons, nerves, blood vessels, or foreign material deep in the wound. Keep your tetanus immunization up to date. If you get a cut, scrape or stitches, follow the wound care instructions to help avoid infection. I've heard doctors say that they practice according to rules, and lawyers that they follow cases.