Merino wool base layer, something like Cabela's Woolmate outer with wind shear. What you put between them really doesn't matter that much. I use a fleece pullover , heavy sweat pants and a light wool vest.

Pack boots like folks waaaaay up north wear with thin poly-pro liner socks and medium - heavy wool socks.

Light wool gloves and a muff with hot hands is the way to go for hands. Ya gotta cut the trigger finger off yer glove.

I use a Carhartt 2in1 head fleece on my noggin' .

https://www.cabelas.com/product/foo...reme-pac-boots-brown/722130.uts?slotId=7

https://www.carhartt.com/products/carhartt-accessories-knit-hats/Fleece-2-in-1-Headwear-A202

The above is for outdoor use and NOT in a plush, climate controlled shooting condo.