If you don't want to spend on expensive down jackets, you can get / borrow a cheaper polyester one (make sure it's long enough to go over your hips) and wear at least 4 layers: - thermal wear, long sleeve t-shirt/knitwear, fleece sweater and the polyester winter jacket. These are must-haves in addition to the above: wool socks, leather / Thinsulate gloves, polyester/wool scarf over the neck/chin+mouth. These were the minimum that I wore when I went up to the swiss alps, but it also depend on your tolerance level (of cold).
Don't buy those woven gloves with lobangs, as they don't work at all, get leather gloves (about $40) or Thinsulate gloves which are available from about $10-$18, depending on sales. If possible, spend a bit more on better quality material which will really do its work of keeping you warm. Hope this helps.
ps: I forgot to add - a wool/polyester cap is also a must have, as we lose lots of heat from the head.