Some simple tips that cost nothing extra:
Cooking
Use the microwave instead of the oven (unless batch cooking)
Put a lid on a boiling pot to cook quicker
Think about recipes and use “one Pot” or Slow Cooker recipes, not the oven.
Only boil water you need for a cuppa. Measure it in a mug if necessary.
Keeping warm
Wear more clothes instead of turning the house heat up
Make the whole family wear VESTS under other clothes. (Buck the fashion trends and be sensible and cosy!)
Make sure there is no air in the radiators (cold spots top or bottom). Contact your Landlord to fix problems.
Fit draught excluders, make door draught-sausages out of old clothes to reduce chilly draughts. (Stuff the old clothes into an old pillow case sausage.
Don’t let curtains cover the radiators, or push chairs up against them.
Dry washing on a rack, not radiator. Better still hang outside in the breeze
Appliances
Turn off all chargers when not in use.
Turn off all appliances that are on standby.
Dust lightbulbs and turn off when not needed.
Bathing
Use a shower instead of a bath
Shower for no more than 4 mins (an egg timer will show you how long)