What kind of evidence do you need to deduct from tax?

[Retard]

Technically, I am self employed, and basically I don't want to pay any tax at all, and would like to deduct everything I spend money on as business expenses, which I honestly believe that they are. For example utility bills, rent, and council tax (as I wouldn't live here if I had a choice), books as I need them to keep entertained, restaurant and bar bills as I need to eat and feel it is good psychologically to have a pleasant life, also any money that I save should really be considered not saving but an insurance expense incase I fail at what I am doing.

What kind of evidence do I need for my claims?

[Retard]

Surely if I had a canteen it would be tax deductable? How is it any differnet if I buy myself food?