One of my favorite quotes is, "Help people get what they want, and you will get more of what you want." A large percentage of our clients come to us because they were referred by a friend who is also a client. People will be much more receptive to you and to your presentation if they know their friend is also a client.
Clients are much more likely to recommend your services when you've provided them with opportunities and rewards for doing so. A successful client referral program begins with you. When you meet with a new client or with existing clients, remind them what you offer, particularly if you have a wide variety of exciting events designed exclusively for your clients.
If your goal is to conduct public seminars throughout the year, consider encouraging your clients to invite their friends to attend the seminar. At every public seminar, there is usually at least one client there with a referral. The client gets to enjoy a free meal and increase their chances of winning prizes.
A client newsletter is also a good way to develop a community and to keep clients informed about upcoming events. I recommend a quarterly newsletter, to start. It could eventually grow into a monthly publication, depending on your schedule.