Look at your budget now, before the weather gets cold. There are lots of things you can do without too much effort.
I take lunch into work every day to avoid buying it. That saves me £3 a day which covers my heating. My lunches are generally left overs home made soup or home made hummus & pittas etc.
What else can you swap - take out coffee ? - I have a little cafetiere in the office and make my own.
Look at your food bill. Eating vegetarian once or twice a week would cut food costs and is easy to do well. Or I've swapped buying chicken breasts for chicken legs. £2.50 for four instead of £6. Learn to take the bone out, and the resulting meat is better tasting and less than half the price.
General care of possessions - getting your winter boots reheeled and repolished can see them through an extra year. Get your winter clothes out now, Replace buttons, mend hems, generally spruce them up to avoid replacing them. Sell anything that you don't want. Buy supermarket thermal tshirts and socks. They are inexpensive and easy to wear under sweaters or jackets.
Look at your insulation? Loft insulation is inexpensive, easy to install and will pay for itself in one or two seasons. Consider adding an extra layer. Can you add thermal liners to curtains - any relatives who know how to use a sewing machine? Draft excluders are cheap too. Rugs will help keep ground floor rooms warmer.