Word-of-mouth is one of the most important ways for a company of any size to gain new business. There's nothing like a positive endorsement from an existing customer to make a strong impression on prospective clients. After all, long-term customers know first-hand the benefits your product or service offers.

Coupled with timely follow-up, referrals can boost your bottom line. Focus on over-delivering to ensure a positive experience and you'll see the benefits.

Here are 11 tips to cultivate positive feedback from existing clients to help attract new ones.

1. Build trust. 

Walt Bettinger, President and CEO of Charles Schwab, wrote an article about the importance of building trust in order to win business: "Building a reputation was something I had to do before I could persuade any company to do business with me." He goes on to say, "You cannot buy and sell a reputation." 

Word of mouth recognition for a job well done, a product or service, is built on the reputation of trust, which takes time, effort and according to Bettinger, a few failures along the way. He suggests embracing defeat, learning from it and making adjustments.   

2. Do a great job. 

This is the foundation for word-of-mouth marketing; fall short here and you not only will miss out on referrals, but people may actually speak negatively about your business to others. Deliver service that's so exceptionally good it gets everyone talking.

Make sure your product and service are first-rate. Avoid spreading yourself too thin by trying to be all things to all people. Instead, focus on what you do best and exceed expectations. A strong, personal referral from someone that knows your value and conveys trust in your ability is far better than any paid ad in a business journal.

3. Ask for feedback. 

Clients appreciate the opportunity to share their thoughts with you. This can happen through a casual conversation or more formally by asking clients to complete a survey about their experience. If they offer constructive criticism, take it to heart and learn from it so you can put even more muscle behind tip #2.

4. Request testimonials. 

If a client gives you great feedback, ask them if you can use their endorsement to let others know about their experience. A one or two sentence statement of their thoughts can be helpful on your website, brochure, social media channels or other marketing pieces.

5. Don't over-rely on social media. 

Social media is important, but don't underestimate the power of a rave review from a customer who speaks favorably about you to their friends. Be sure to have plenty of real-world interaction that will help fuel exposure and good feelings when people see your authentic, genuine self in person. A positive impression will work to your benefit in the future when they need your services.

6. Find a high profile satisfied customer. 

If a person is happy with your services, they often aren't afraid to shout it to the moon. Imagine if that person is highly respected in your community or the world. Getting an endorsement from someone that people admire is a golden opportunity to have your business profiled by a leader or celebrity who others trust and want to emulate.  

7. Generate referrals. 

If you have customers who are happy with your work, ask them if there are others they know that might benefit from your services. They may be willing to share some of their contacts who are a good fit for your offerings. It may feel awkward to request a referral, but they may write a letter on your behalf as an entree to your services.

8. Give back. 

Get your business involved with the community. Whether it's hosting a drive for the local food bank or helping to build a house, you create visibility for your company that lets others know you are working to make your community a better place. That can be an important way to distinguish yourself from competitors.

9. Emphasize relationships. 

Don't forget a customer once the job is over. Continue the relationship with them so the next time they need what you offer, they will think of you. This can include staying in touch online through an e-newsletter or more traditional methods, such as a direct mail piece with information on specials.

10. Be responsive on social media.

It's not enough to put up a Facebook page for your business and be done with it. Post news and updates frequently to let clients know you are there - you don't want prospects to see that your last interaction was six months ago. Monitor feedback from your followers and answer questions promptly. This is another way to show that you are focused and engaged with your clientele.

11. Say thank you. 

When you get a new customer, ask how they heard of you. If it's a referral from an existing client, be sure to thank that person for recommending you. Send them one of your leading products as a thank you, or drop a note into the mail. Let them know how important their referrals are to your business, and that you are happy they have had a good experience with your company. This can be done via a phone call, a handwritten note or even a gift if they send you a substantial piece of business.