Having good debt records is essential for many reasons: proving eligibility for student grants, becoming eligible for medical cost discounts, and applying for home or commercial loans.
First, make a list of all of your debts. This includes consumer credit such as vehicle or boat loans, credit cards, and unsecured or secured loans from banks. Bank statements and loan statements are the usual means of proof for these debts. You may also have to provide the actual promissory note, so keep that with the bank statements.
Another category of debts would be commercial loans. These include small business loans for equipment or operating capital, and real estate loans. While bank statements are preferred to show this debt, if the loan is new, the actual loan document is fine, too.
Payday loans can be validated only by the promissory documents provided by the lender. This is also true of any other short term, unsecured or secured loans.