When a lot of people are first hitting rails, their first instinct is to lean back on their edges, because that makes them feel comfortable for some reason i guess. this makes them slide out and have a bad time landing on their back on the rail. the trick is to keep your edges perpendicular to the rail, and the bases of your skis flat to it-not leaning down the rail or back. I don't remember what the first kinked rail I hit was but I remember that if you just keep looking and let yourself kind of naturally adjust it wasn't hard at all
good luck!