How To Write A Letter For Volunteering . Here is another sample of motivation letter for volunteering, which can be written as an application to apply for a particular working post in any organization. What to include in a cover letter for volunteering include relevant experience. request for volunteer letter sample Google Search Sign in sheet from www.pinterest.co.uk At the beginning of the document, include the recipient's address in the top left corner. Use professional cover letter spacing: A 1” margin on all sides and single or 1.15 line spacing is perfect.