Really? You already know you're wasting two thirds of your electricity? If I had to cut consumption by two thirds I'd be sitting in the dark a lot. Do you have an example of what you'd cut?
Heating, air conditioning, refrigerators, washing machines, tumble dryers, dishwashers, hobs or ovens are typically responsible for more electricity consumption.
Personally, since I don't have air conditioning, only use heating ~3 months a year (I live in a very mild climate) and almost don't use the tumble dryer, I would have a very hard time cutting my consumption by two thirds. Maybe not using the dishwasher, washing clothes less (or by hand) and cooking less, but probably it wouldn't be enough.
That’s just in the home.
All would involve sacrifices, but doable ones without having to live in Mad Max.
If you want to simply save energy, avoid the car. It's really apparent if you have an electric car because you have units that you can compare with other things, but for example, we burn probably 6 kWh per day in the car and this absolutely dwarfs our daily consumption in our apartment. If it's close enough to walk, then walk it.
Just dryer and car may get you close to your goal.
Arent these just displacing your electricity usage? I assume you aren't going to have less showers for example. And I can't see a trip to the coffee shop or cinema being 'greener' than the stay at home equivalent.
And, well, for tips, a washing line. There is no need to tumble-dry anything, a piece of rope, some pegs, and wind and relative humidity do a pretty good job themselves.
Do all of those and cutting your emissions by 2/3 is very easy with most of your quality of life intact. Big homes, cars and flights don't make people happy, so moving to such a lifestyle wont be a catastrophe. I am not sure why so many in the western world dreads it.
[1] https://www.ovoenergy.com/guides/energy-guides/how-much-elec...
I'm very surprised by and suspicious of lighting being 600 kWh/year, so I question their sources or analysis. They note themselves LED lights are around 6 kWh/year.
Edit: Their source appears to be a 10 year old survey from before LEDs being generally available in shops, and before tungsten was banned from general sale. No wonder the numbers are off.