Don't be a yes person. Believe it or not, customers don't want to hear "yes." They want the truth. If you are a yes person, you could be setting your customer up for expectations that you or your product can't meet. If you want to provide great customer service then explain to your customer exactly what they are getting and do so without any exaggeration.
Be available. Customers hate voice mail. I hate voice recordings. We know the work place is now a global one. If you are out of the office, still leave a way for a customer to reach you. Keeping customers happy means being available when he or she needs you the most- which can interrupt your vacation. But, wouldn't you rather come back to the office with happy customers that can refer you out vs. unhappy customers who can use Google to review your lack of response?
Creativity. If a customer is having a problem, don't spew policy at him or her.Take ownership of the problem and personalize how you are going to make it better. We are all individuals. No one wants to be treated like an account or a number. Don't ever spew policy, spew answers and apologies.
Striving to provide excellent customer service will be one of your greatest tools when it comes to growing your business.