From bottom to top: ski socks. Then for pants, base layer. Either moisture wicking leggings or long underwear of some kind. You'll tuck this into your socks and have all of this inside your boots so make sure it's not too bumpy or bulky. Depending on temp and the warmth of your snow pants, bring a second baggier pair of pants to put over the base layer. Sweats or pajama pants do the trick. These outer pants and your snow pants will get pulled down over the outside of your boots. Up top, a moisture wicking long sleeve or turtle neck. And again, depending on the temp and the warmth of your jacket, you may want a second sweater over that, I like a quarter zip fleece. If it's really cold, you may want a baggy hoodie over all of this. Then your jacket. I'm a big advocate for layering on your hands too. I usually do a thin pair of texting/driving gloves under a pair of mittens. Mittens will always be warmer than gloves. Then on your head, bring a couple neck warmer/balaclava options and see what feels best. These are going to get wet with sweat, snot, spit (yeah it's gross) so have a backup. Also consider a thin hat for under your helmet.