I was exactly the same with never really knowing where the money had gone each month! The best thing I ever did was get Monzo. I have about 6 different pots and when I get paid my salary automatically gets split between them – mortgage, bills, credit card, holidays, birthday/Christmas presents, savings etc.
My mortgage and bills then come directly out of their pots, so I know the money left over is actually available to spend rather than mentally having to remember what’s still due that month.
The spending tracker is really good too because it makes it painfully obvious when you’ve somehow spent £££ on eating out or random shopping 😂 Honestly recommend it to everyone and have set my auntie up on it who is now a pot convert.
Snoop is also really useful if you don’t want to change banks. You connect your accounts through Open Banking and it pulls everything together so you can see where your money is actually going. I’d probably do that for a month first because with £2,400 left after bills/savings there might be some really easy wins once you can actually see it all.
Then for little savings on things I’m buying anyway, I’ve started using Sprive. You buy gift cards and the cashback goes towards overpaying your mortgage. I’ve used it for Airbnb is currently 5.8%, but I’ve spotted Jet2holidays at 9%, Lastminute.com holidays/hotels at about 7% and some of the spa/theatre ones are over 10%. Definitely worth checking before booking a holiday or anything expensive.
My Sprive referral is below if useful
https://linkprod.sprive.com/refer?code=JM06ZHFZ
But I’d definitely start with Monzo/Snoop and work out where that £2,400 is currently going. You might find you can build the holiday pot without feeling like you’re massively cutting back.
good luck! ☀️