Know your spam rules. A lot of innocent people send spam because they didn't know any better. Read up on the CAN-SPAM act to avoid any trouble. Put simply, you're allowed to send bulk email only to people who specifically asked to be on your mailing list. If you collected email addresses for a lunch giveaway or an event invitation, then you don't have permission to send marketing emails unless you made that clear at signup. Include an obvious unsubscribe link in every email, and don't forget to remind subscribers how they got on your list in the first place.
Technology has a significant impact on consumers’ expectations, and those expectations impact how subscribers engage with your email marketing. Brands need to continually demonstrate that they know their customer, which can make it a challenge to stay on top of the evolving context of marketing. An email strategy can make all the difference between building a relationship with your customers and sinking without trace.