We batch book to save energy costs (I'm lazy so quick cheap dinners) and we usually save making the big pot for a very cold day to warm the kitchen up.
We used to have a small kitchen with no space for table and chairs but now we have a larger kitchen and can fit a table in there so we spend a lot of the winter in there because it's the warmest room in the house due to cooking. Hot porridge for breakfast on the stove top. The few mins of having the hob on helps take the edge off the house in the morning and because it's an electric hob the hot plate stays warm on top for ages.
(we rarely put the heating on for money reasons anyway, also good for the environment)
We did invest in electric blankets for some of the beds, children all share a bed in winter to keep warm. Sometimes I come in too if DH is working away from home. We took one off the bed and put it on the sofa instead of buying a heated throw which are way too expensive. That keeps us from going to bed at 5pm every night.
Children have a bunk bed so we tuck blankets in the top bunk to make a den that's so warm in there. It's sort of like Ebenezers bed in the Disney Christmas Carol. 4 poster beds with curtains were to keep warm. It works well.
For children, I keep a pop up tent with blankets and pillows and a hot water bottle. it's the option if a nice heated area for them. I wish I could fit. We used to use lots of hot water bottles and if you keep them wrapped up in a blanket they stay warm for ages.
What we couldn't afford before but can recently is curtains. We got loads second hand and this winter is going to be so warm.
I was looking at thermal lining but I think plastic insulates really well so I'll be looking at shower curtain lining, you know the plastic white sheets you can get to go behind the pretty curtains? if that's too expensive I'll just pin up spare duvet covers to thicken up the curtains.
In times old we just nailed up blankets to cover window.
Also keep the oven door and grill open after cooking.
fluffy socks for kids, slippers for adults. House coats on always. We have some thick pyjamas too which we basically live in all winter. only get dressed to go out.