Commercial email ACT

Copied from, http://business.ftc.gov/documents/bus61-can-spam-act-compliance-guide-business
Summary,

• Use proper header,Your “From,” “To,” “Reply-To,” etc should true not fake.

•  Subject should not be misleading. 
• If your email is ad, then clearly disclose that your message is an advertisement. 
• Tell recipients where you’re located. This can be your current street address, a post office box you’ve registered with the U.S. Postal Service, or a private mailbox you’ve registered with a commercial mail receiving agency established under Postal Service regulations
•  Any opt-out mechanism you offer must be able to process opt-out requests for at least 30 days after you send your message. Give Un-subscrition option and that email should not be block by our own server (like as spam). Also give options to select how to receive future emails. That should be clear (font, color, etc). You must honor a recipient's opt out request within 10 business days
•  You can't sell emails to anyone.