Never provide personal information (e.g., passwords, credit card number with all details in one email, etc.) to anyone through email communication.
You are most secure when you start at the homepage of your service provider (e.g., mail.google.com).
If you receive a suspicious email, do not click on any links or reply. A suspicious email would be one that doesn't include normal brand heading, has typos and errors, or asks for personal information via email.