Current Account - living expenses - all direct debits for rent, utilities, bills etc paid from here (Currently First Direct)
Yes, good idea.
Savings account - 20% of earnings paid via Direct Debit to savings account (Currently First Direct)
Consider an interest paying current account if you can meet the eligibility criteria, such as TSB Classic Plus. It can pay around 3% on first £1500.
How much do you plan on having in this account? Three months of expenses, six months, more?
Considering doing the following:
Money allocated to ‘Pots’ - multiple interest paying current accounts for different things ie holidays, Christmas, car maintenance, household etc - good idea or pointless?
Good idea but you could do it on paper (literally in a notebook) or use a spreadsheet to track the pots. Some savings accounts let you have multiple pots within them... not sure which ones, with luck someone will read this and know more about that.
Cash ISA for medium/longer term personal savings (instant access or fixed)? Do you review every year and change if better interest is offered elsewhere?
I would not bother with a cash ISA. The interest paying current accounts pay more interest. You don't pay tax on interest now until it reaches £1000 (£500 if higher rate tax payer), so given the low rates it could be a while until you get that much interest in a year.
www.gov.uk/apply-tax-free-interest-on-savings
Look at Stocks & Shares ISA - you could invest in a couple of index tracker funds which would be fairly safe... though of course everything does go up and down but you did say Long Term so I presume you are talking 5 years+.
You could also try some fixed term products such as those from ATOM bank, NS&I, where you put in an amount and leave it there for a fixed period of time.
Cash back credit card - buy everything on it and pay off in full every month?
I would avoid the temptation of using credit. Just use debit cards. If you have to have one, then just have ONE.
Credit cards old and paid off - keep open for good credit
No, close them.
I would still keep things like a mobile phone contract. Utility bills and council tax in your name, on electoral role and be saving for buying a home with a mortgage (payment around 25% of your take home pay).
Do I need to track every individual personal expense in a spreadsheet i.e 20.06.18 Petrol station £1.50 Newspaper?
YES. It can really help to start with. I was spending over £400 a year at Starbucks. Tracking spending for a month, or two, can help you identify things you spend money on which you don't need to be doing. You can then put that money to better use, such as your savings, investment and pension.
Pension contribution - how much, how often?
Does your employer offer a workplace scheme - most do now.
I would join that scheme and contribute up to the amount the employer matches. That may be quite low now, around 1% of earnings for small employers but it does go up over the next couple of years. I would aim for putting in 15% of your gross income (ignoring any employer contribution) however I would only do that after you have cleared any existing debts and have a good 3-6 months of savings (for a rainy day).
My strategy is based on the Baby Steps by Dave Ramsey.
If you like that idea and wish to do it, then there is a UK support group on Facebook
www.facebook.com/groups/1625701281083011/ and you can buy the book, borrow it from some libraries, listen to it on Audible.
As Dave says in the video, read books about money - anyone's books. The more you learn the more you will be in control of your money.