Email marketing was already old before social media marketing came of age. It's a testimony to the efficacy of this mode that this continues to be an important channel for millions of small businesses. Email marketing lists are considered priceless and businesses go to great lengths to develop and maintain them for two reasons: sales and more sales.

Here are seven small business email-marketing ideas that will drive qualified, in-the-mood-to-buy traffic to a company's website.

Related: The 8-Second Challenge: Email Marketing for Our Shrinking Attention Span

1. Make the sign-up process easy. Place a sign-up box high on the company's website and add a link to the email-marketing signup page on the organization's social media profiles. This can serve to drip feed a steady list of new prospects.

2. Grab the reader’s attention from the subject line. Start with a compelling proposition: a teaser, giveaway or discount. Try to hook readers from the beginning so they'll read till the end. Oh, and do this so the email isn't snagged by the spam filters.

3. Stay compliant. Stay on the right side of the email service providers. Do not violate the Controlling the Assault of Non-Solicited Pornography and Marketing Act of 2003. Email service providers offer tools and learning resources; use them. Know the difference between a “hard bounce” (the message won't be delivered because of a problem with the email address) and a “soft bounce (the message hasn't been delivered yet but might be later on).  

Related: Want to Make Email Subscribers Unhappy? Do These 6 Things.

4. Develop the audience. What sources are generating the most responsive audience members, the kind who open, read and click on the links of newsletter? Work further on those sources to build the company's email newsletter list. Try a double opt-in process since it ensures that the subscriber truly wants to read the content and the newsletter will go to a working email address.

5. Use best practices. The most effective calls-to-action go above "the fold," the area of the message that shows up on a computer screen, without a user needing to scroll down. Also emails without a lot of images generate a higher return on investment.

6. Be brief. Test and tweak until arriving at a satisfactory combination of format, structure and tone. Brevity is valuable; learn to say more with fewer words. Look up Elmore Leonard’s 10 Rules of Writing about how to create crisp content. Readers might just scan an email newsletter. Pack in words with special meaning and use subheadings.

7. Keep the communication going. Judiciously use automated replies. Auto-replies are time-savers, providing useful information, nudging readers toward downloads, reminding them about freebies -- all while generating information on subscriber behavior. Service providers range from MailChimp and aWeber to the more advanced and feature rich such as 1ShoppingCart and Infusionsoft. I personally use 1ShoppingCart for its all-in-one customer-relationship-management, email and ecommerce solution provided with ample customer support. 

Related: 5 Ways to Build Trust With Your Company's Online Audience