Smile, and provide service.
In the retail world it is important to greet customers, smile and make eye contact, sometimes giving your name and offering assistance. When working with colleagues it means making the time to develop a relationship, understand their needs and getting work done on time.
Maintain Approach-ability
When shopping we want service professionals to be visible which is why many stores require uniforms for us to identify resources as needed. It is also important for us to make ourselves approachable at work to co-workers even if we can't help them at that exact moment.
Inquire and listen
You are in business to serve your customers, and you can only do that if you know what it is your customers want. When you truly listen to your customers, they let you know what they want and how you can provide good service.
Be a good listener. Take the time to identify customer needs by asking questions and concentrating on what the customer is really saying. Listen to their words, tone of voice, and body.
Locate the Answer
You don't have to be an expert at everything. Making up an answer to a client's question can make the problem worse. Don't be afraid to say "I don't know" but be sure to say when and how you will respond.
Express appreciation and follow up.
Too often we are quick to criticize and slow to praise. Catch your employees doing something right. Employees are your internal customers and need a regular dose of appreciation. Thank them and find ways to let them know how important they are. Treat your employees with respect and chances are they will have a higher regard for you and your customers. Appreciation stems from the top.
Needless to say applying these principles will do wonders for your personal relationships as well. 
in Human Resources and a 6 Sigma Greenbelt. 