The main thing would be to keep it quiet and isolated from other chicks as they would peck at the rawness. I've found you can place them in a small Tupperware container in the incubator (lid off, of course) or even an empty yogurt cup if it's a small chick. Hopefully the umbilical sac/hernia will pull in in a day or two. The isolation will also allow the chick to catch up to being a chick... Looks like he was a tad eager to hatch!