[header] How to avoid the gmail spam filter [title] Create your own email list. [step] Rather than purchasing an email list from a third party or using a robot, build your list from scratch. The only people on your email list should be people who want to receive your messages. 
[title] Let your recipients double opt-in. [step] Even if the only way to be added to your list is to sign up online, make sure your mailing list service delivers a confirmation message so the customer (or potential customer) can confirm their membership.