Anything that heats up chews through electric, so electric radiators/heaters, tumble dryer, electric cooker, hairdryers/straighteners, kettle, immersion heater etc etc.
Things like tvs & consoles and blenders will use a medium amount of electric.
Things like phone chargers and low energy light bulbs only use a low amount of power.
You could get an energy meter like an OWL that tells you how many watts your house is using at any moment. Some libraries lend them out. Have fun & go round the house switching things off & on to see how it affects the owl reading :)
Check your immersion heater isn't permanently on, just put it on for 45 mins before you want a bath or 15 mins for a bit of washing up.
Check electric heaters aren't left on when/where they're not being used.
Wash on a lower temp & hang dry your clothes if it's a dry day.
Make a small mark (or mental note) on the side of the kettle where each mug of water comes to. Only boil just enough to make the appropriate number of teas.
Try to double up things in the oven, cook tomorrow's lasagne with today's pie... it will just need a quick reheat in microwave.
Put lids on saucepans and turn the heat down. If you're cooking pasta, you can even switch the heat off once it's a rolling boil, just cook for a couple of mins more.