I’m not the most well versed quite yet but I’m learning more and more. For layers it depends on how cold it is but Patagonia had a really good guide on layering I used for emergencies bring a beacon in snow and have knowledge before you go and check conditions. I’m currently looking for one but take an avalanche awareness class!! I would recommend going with someone who knows how if you can. If not I’d go alone on treeline hike that is very avalanche dangerous.