Entry is typically made by leaving a comment on the giveaway post. A limit of one entry is allowed per e-mail address. You may not enter more than once, whether or not you use a different e-mail address. Subsequent entries determined to be submitted with the same email address or from the same individual using multiple email addresses may be declared ineligible.
You may, however, obtain additional entries on a particular giveaway through other channels when applicable and prompted (i.e., by performing an action such as posting to Facebook, mentioning on Twitter, or blogging about the giveaway).