First you need emails, right? Hopefully you've done a great job of acquiring your customers email addresses. How do you get more? Ask if you can send your free email newsletter whenever you encounter a potential customer - at local and national events, through a link button on your website or other sites, when you talk with potential clients on the phone, at the dog park, at your local pet store - anywhere you meet potential customers throughout your day, just ask!
One of our favorite email newsletter services is Constant Contact. Not only is it customizable, easy to use, and flexible - they offer a 60 day free trial, and it costs very little per month after the free trial period ends. We've been using it for nearly three years and have always been extremely happy with the service and the results.
If you're not using an email newsletter, we strongly suggest you give it a try! With a 60 day free trial, you have nothing to lose, but a little time to put it together.