I wear either: two hats and a neck gaitor or a full face mask and another hat on top of that. Your head has to stay warm or you'll get cold. I see these guys on tv hunting in bone chilling cold with a baseball cap on!! Give me a break!! I also have used the big insulated things you pull over your boots once you get on stand, even without heat packs in them your feet will stay very comfortable. I have some Saddlecloth pants (not insulated) that are sufficient by themselves down to 20 degrees or so, below that and I usually wear a pair of long underwear (Duofold) also. I wish I could find clothes in Saddlecloth again because it is the warmest and most durable fabric I have ever found (it doesget a little noisy when it's cold but it is stillmy preferred clothing).

One more thing that works wonders for me: bring a small thermos of hot chocolate on stand with you, you won't believe how much that warms you up when you take a few sips. Trust me!