How To Write A Letter Confirming Sponsorship . Begin the letter with your intent, describing your reasons for sending the confirmation candidate the letter. Sure to have the letter to them in time for that. Sponsorship Letter for Event Template Format, Sample & Example from www.pinterest.es Corporate sponsorship letter step #2: This individual sponsor can be your family, a friend, a relative, etc. Start the letter with the date, and then the sponsor's name and address.