The correct way is mentioned by Allah in Surah 2:282-283. (1) To specify the period of the loan that must be repaid. (2) Writing down the loan. (3) If the one who writes down the loan is a person other than the debtor, then the debtor is the one who should dictate to him the details of the loan. (4) If the debtor is unable to dictate because of sickness or some other reason, then the one who should dictate on his behalf is his guardian. (5) The loan should be witnessed by two men, or one man and two women. (6) The lender has the right to ask the borrower to guarantee the loan with a pledge, which the lender will keep.