Not sure if they have this over tehre, but here you can get this plastic wrap stuff to put over your windows (on the inside) that keeps the heat in and prevents drafts.
https://www.creativehomeowner.com/index.php?pane=project&projectid=chwin232
.... I'm thinking of doing it this winter, because there's an awful draft from our bay window in the living room. it's covered by curtains anyway and I usually leave them closed for privacy, so it's not visible on the outside and won't be offensive on the inside either. Aside from that, we keep the furnace set a couple of degrees lower and wear sweaters/socks/slippers/etc in the house.
Rather than using the big oven I'd often cook in the toaster oven if possible, since mine had a broiler setting and it uses way less energy (it's since bit the dust lol but it saved so much money!!)
We switched to HE washer & dryers which made a big difference too.
On the beds, when it's cold I keep the mattress cover, fitted sheet, flat sheet, a blanket, then the comforter on top so we have layers and can use as many/as little as needed. I put an older rolled up blanket (as in doesn't match my living room to use as a throw) along the door to prevent a draft...
We use HE lightbulbs and have flourescent lights in the kitchen and basement. I turn off power bars and leave lights off as much as possible, etc.