We live in a pretty fast-paced, technology-driven world. We rely heavily on technology to be successful in our personal and professional lives. That being said, at the end of the day, we're all guilty of feeling nostalgic at one point or another about certain tendencies and routines of the past.

In business and in life, saying the words “thank you” can be extremely meaningful and powerful for all parties involved. One of the best ways you can boost customer loyalty and land new customers is by expressing appreciation and gratitude to those who choose to buy from you and work with you—after all, your business can't survive without your customers.

If you really want to impress and surprise your new customers, send them a handwritten letter or card thanking them for their business.

Sending handwritten letters to each and every one of your new clients might not seem like the best use of your time or money, but what a lot of startups have found is that it's actually an incredibly simple and effective way to boost customer happiness, build loyalty, and transform passive customers into engaged advocates of their brand and products.

Not quite convinced that this tip is worth trying? Here are real examples from four SaaS startups that regularly send out handwritten letters to customers:

• Handwritten Letter from CoSchedule
• Handwritten Letter from When I Work
• Handwritten Letter from Stride
• Handwritten Letters from Buffer

Here are the three steps you should take to implement this growth tactic:

Step 1: Compose a few templates you can use when it comes time to write a thank you letter to a new customer. Include a few spots in your letter where customization/personalization can be added.

Step 2: Develop a process or plan for sending out thank you letters to new customers. Your letter should be sent within a week of your new customer coming on board. If your business is still small, you can handwrite and send the letters yourself, or have one of your employees help you. If you're growing too fast to send manually, hire a freelancer to help you, or use a tool like MailLift or Handiemail.

Step 3: Buy materials if needed (cards, pens, envelopes) and start sending out your thank you letters.

ProTip: Don't be afraid to ask your thank you card recipients to reach out to your company on social media to let you know they received their card! They'll be excited to snap a photo and share with their followers, and it's free word-of-mouth marketing/advertising for you. After we started asking people to share our cards on social media at When I Work, we saw a 37% increase in overall engagement and mentions of our company from happy customers on Twitter.

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