Aid in company closure - UK only

Our client / associated company will be looking to close it's books. It has several loans, all on the same basis. They are private loans that are not repayable unless the company has the funds to repay them. The company has some funds, but not sufficient. As such the majority of the loans can be written off. The company needs detailed step by step instructions on how to write these off in the accounts without unneeded expense, without paying more tax than the minimum required and without violating any laws. If you are experienced in UK accounting and tax law and can provide solid guidance to this closing company please bid.