Email Etiquette Email etiquette is the set of rulesĀ to write appropriate and effective emails.To master email etiquette, you should learn at least the basic principles of every main etiquette category:Email recipients.Email content and form.Appropriate use of email. Email Recipients Etiquette How to appropriately manage your email recipients. Email Content & Form Etiquette How to write emails in the proper form and avoid inappropriate content. Appropriate Use Of Email How to effectively use email in the most common situations.