Understand the concerns associated with e-mail -- First you should understand some of the privacy concerns that may be associated when communicating online via e-mail. More Information.
Know the recipient -- Make sure that your e-mail recipient is a trustworthy person and will not forward your e-mail on to others without your consent.
Use a password -- If you share your computer with others - such as family members or roommates - use an e-mail application that can be password protected.
Use Web-based applications -- Using Web-based e-mail (like Hotmail or Yahoo) may be a good approach if you're concerned about people who have access to your computer reading your locally stored e-mail.
Delete local copies of messages -- You can also delete the local copy of your sent e-mail message by opening the "sent" or "out" folder in your e-mail program and deleting the message. You will also need to then open the "deleted" or "trash" folder in your email program and delete the message one more time to make sure that it is removed from your email application.
Learn more about unwanted e-mails -- You can learn more about unwanted e-mails. Visit spam.GetNetWise.org