Hello Atinuke,
I am new my self. This is not advise it is just the way I think I am going to do it. I havent tried yet, it might go wrong, if you try it and it does I will not take responsibility. I think it comes down to income and expentiure. All you are trying to do is look at your bank records, any thing that comes into your account is income, any thing that goes out is expenditure.
A simple way, might be to download the CSV from the bank onto a spreadsheet. Do this in your online banking account. Delete off any entries that are irrelavent eg shopping in M&S while it is in spread sheet form. Be careful not to disrupt the column line up.
Download their manual CSV sheet which has again got something like two columns. You can find that on here.
Copy off your banks CSV which you have cleared of rubbish and put your income into the income column and the expenses in the expenses column for the period. Upload their sheet back into their system.
When it is in their system tag all the different incomes and expenses using their tags, I intend to put the ones I use regularly on a word docment and copy and paste them again and again.
This should transmit everything into the right place.
Upload the relevant timed period to the inland revenue at the right time 4 times a year
You are not trying to create a tax return 4 times a year, just a mini report of income and expenses.
At the end of the year they will use this info to create a return. Have a look at it online in the inland revenue website and then make amendments and add stuff they havent put e.g particular personal allowances which might not be included.
If it goes wrong, you use this method at your own risk.