I actually run a company and have staff etc to do that but I suggest you contact HMRC's advice line/bot to see what is possible.
Ask it/them whether you can claim for your own time doing your own accounts. To make this possibly work, you will need to do the work out of your regular employment hours. I suggest you could allocate say two hours per week on the weekend. Set a reasonable rate for the work: at least minimum wage but not excessive. You are probably not an accountant so charging yourself at an accountant's rate would be daft and considered excessive. £20ph seems a good start. Make sure you do actually stick to doing the work at the stipulated time or at least you are "in work" at that time - so your laptop should be running and logged in even if for a couple of weeks you are watching iPlayer!
The work is recording expenses/transactions, maintaining records and preparing data and recording it for online taxation requirements imposed by HMRC. That's a start - you'll come up with something better.
The above assumes that you do self assessment and that the flat £1000 expenses a year thing is not suitable for you. It might be best to hire an accountant instead but bear in mind you can only claim back the taxed portion of their fees.
eg You earn £10,000 over the untaxed allowance - that £10,000 will be taxed at 20% (1) ie £2,000. You hire an accountant who charges you £1,000 and saves you £500.
So the tax you pay is: (10,000 - 1000) x 20% = £1,800. The accountant saved you £500 by being an expert so it looks like a bargain: you paid £200 less to HMRC because you hired an accountant. You saved £500 via their advice. So that's a saving of £700 - lovely!
However, you paid the accountant £1,000, so you are £700 up and £1000 down = £300 down.
I've made a few assumptions here but a few minutes with a spreadsheet and a close reading of (1) will soon find where the point of hiring an accountant kicks in and how much you will want to pay for them.
(1) https://www.gov.uk/guidance/rates-and-thresholds-for-employers-2025-to-2026