3 layers plus a fleece when I go to my allotment, always a thin silk vest as the layer in contact with skin, then a cotton polo neck to keep my neck and back warm and a thin warm cotton french terry sweatshirt. Tights, socks and denim jeans and warm insulated boots. This combo works very well at 4 degrees outside
Out of that lot, the items that work best are the silk vest and warm tights so when I arrive home, I change into silk vest, a fine ribbed jersey polo (I made several from `meet milk` fabric) and a warm hand knitted jumper made from merino wool. I take the jumper off if I get too warm but that combo keeps me very comfortable. I team that with a flannel skirt and warm tights. It all works together to regulate my body temperature. Man made oil-based fabrics do not regulate my body temperature at all, they make me either too hot or too cold