When used correctly, email marketing can increase sales, keep customers interested in your brand, and dramatically improve your overall ROI. When used incorrectly, email marketing can annoy, bore or even repel people from your business.

Follow in the footsteps of companies doing email marketing right with these four examples...

1) HuckBerry: Sell and educate your subscribers.

 Many email campaigns fail because the main goal is to sell. So the marketers end up treating their subscribers like ATMs instead of actual people. On the flip side, you have brands like HuckBerry, an ecommerce store aimed at the rugged modern male, which have figured out how to provide value, and sell at the same time, through email marketing.

HuckBerry's emails blend both creative storytelling and sales pitches to create more than just a simple email. They know their target demographic so well that they share curated content, blog posts and even images that resonate with them while, at the same time, build the HuckBerry brand.

2) Dollar Shave Club: Make them laugh and they'll keep coming back.

One of the best ways to build a brand, in general, is to have customers associate it with positive emotions. Dollar Shave Club does this perfectly with humor. Open almost any of their emails and you'll be hard pressed not to at least chuckle when you read it.

Studies have shown that humor in marketing allows consumers to understand your message and process the information easier. In the above email, you can see that Dollar Shave Club effectively uses humor to get across their unique value proposition: "stop wasting time buying razors and let us ship them to you".

3) Uber: Personalization and localization helps build relationships.

The key to successful marketing is building trust with your consumers. You build trust by first building a relationship. And relationships are built by first knowing how to connect personally with your target audience.

Uber, rather than have one massive email list, breaks down their lists by state. While it's a lot more work, it gives them to ability to speak to their users on a more personal and local level.

Take a look at the above email I received from Uber when NJ Transit, the transportation service throughout all of New Jersey, went on strike. They used a local approach to email marketing in order to identify and solve a major pain-point in my life. They were able to take a bad situation and turn it into a win-win for both their company and for me. I get to go about my day normally without having to worry about transportation and Uber gets my money. All because of a personal and local approach to email marketing.

4) Moz: Curate content to become respected in your industry.

Moz is a SaaS company that offers a suite of digital marketing tools. Like many other SaaS companies, they could send an email blast out every time they publish a new post on their blog. But then they wouldn't be on this list, would they? Instead of solely promoting their own content, Moz uses their platform to curate the most interesting marketing content on the web and package it in what they like to call the "Moz Top 10".

At first glance, it simply looks like a list of links. However, it's much more. It's a list of blog posts, guides and videos that were vetted by top marketers at Moz. Because of this newsletter of curated content, they are more likely to be viewed as industry experts for providing a simple, highly valuable resource.

Published on: May 31, 2016
The opinions expressed here by Inc.com columnists are their own, not those of Inc.com.