The loyalty (and great word of mouth) generated will pay off handsomely in ways you can't even imagine. One of the most important parts mailing list of marketing your business will be to get in touch with your ideal client, and then to continue to maintain regular contact with them. It is essential that you build a relationship with your 'people' so that they will want to buy from you.
Building a relationship of course begins first by finding your ideal client, but after that you want to build the know, like and trust factor (KLT) with them. Once they know, like and trust you, they will be more likely to buy from you. One of the mailing list best ways to start to build that relationship is to send out a regular newsletter like this one! The first thing you want to determine when you are setting up a newsletter is what kind of content you will have in it on a regular basis.
Determining this will be almost entirely based on what your ideal client wants to read about. Newsletters really are a dime a dozen these days and everyone's inboxes are so filled up with so many things, that you will want to be sure to mailing list provide good content for your audience, so they don't unsubscribe. A great newsletter layout is one that is similar to this newsletter: a personal note from you at the top, a feature article (or tips), and then something you recommend.