The Omni-Channel: Not Just for the Big Boxes
The most important element in the process is the collection of customer data: emails, cell phone numbers, Twitter accounts and any other methods through which you can communicate with them. Incentivize them to give up that info with special offers that are only given to valued customers, such as invites to exclusive in-store and third-party events, new product/technology sneak peeks and demonstrations, etc.
Explain to them that the most effective way you can make them aware of those exclusive offers is through that type of communication. Show them examples of what they'll be receiving. Explain to them how the whole process is designed to make it easier for them to receive your goods and services, and to save them time and money doing so.
And make sure to reciprocate. Let your customers know that they too can interact with you through those same methods: text, voice, social media, email, etc. Prove to them that you can respond and react to their requests. If you don't, your competitors will.