Breaking the Ice!!!
Firstly, you should have your research properly done, know what they are like, know what they prefer etc.
Next, Take time to get to know them, share somethings about yourself, interact personally.
To get a conversation going, try to find a common ground between you two. The sense of contennectedness this gives is very valua, It creates instant rapport between you. Use open-ended questions, give them an opportunity to express themselves, thus giving you a chance of discovery.
Add a personal touch
Regardless of which client you’re dealing with, treat all of them as your important ones. You never know who your clients may know or to whom they will refer you. Remember the small details, like how they like their coffee or even their children’s names.
When a client e-mails you, acknowledge the receipt of the e-mail as quickly as possible, even if you do not have the answer they are looking for. You will give them comfort by simply acknowledging the receipt of their request and by communicating that you’re on it.
Basically, you need to reflect the body language and expressions of the person. You have to acti like a mirror but remember not to do this too much as this may come off as mocking or just look weird.
After all this, remember humor! What this means is iff you find yourself stuck and running out of topics, attempt your level best at being the joker.