Use An Accountant
FGM
You may want to think about saving yourself the headscratch and employ an accountant. You can then put his/her 'Professional Fees' against TAX.
I have found it money well spent in the past. A good one will normally get you more than expected and stop you from coming to the TAX mans attention by stopping incorrect returns being forwarded. He is also less likely to question a chartered accountant.
Be prepared, it's not your next return, or the one after that but up to 6years later that you could become the focus of a random TAX investigation.
So...get your house in order by keeping accurate records, getting an accountant to draw up a financial statement for you and have them file your SA may save you a lot or heart ache in the distant future.