you can let your friend write a "Credit Card Authorization Letter" with the card info, his/her basic info and signature on the letter...
[media]http://permittingservices.montgomerycountymd.gov/permitting/pdf/DPSCreditCardAuthorizationForm.pdf[/media]
[media]http://www.cinefilmlab.com/download_forms/creditletter.pdf[/media]