It is highly important on your part. In order to see to the fact that you can impress your client with your person you have to maintain a professional touch in your behavior. There should be an enigmatic appeal in the persona that you don in front of your clients. However at the same time you have to maintain a pleasing friendliness in your persona. It is in fact a great asset. If you can exercise the friendliness aspect in proper fashion it will be a much easier act for you to get your clients properly. However as you try to become friendly make it a point that you do not tend to become too much friendly or over gracious with your clients. You need to strike a balance and there will be no dearth of regular clients.