By Jared Atchison, co-founder of WPForms

As a professional, you want to ensure every single email you send has a purpose, speaks to the recipient and gets your message across. Email marketing gives you easy access to your audience and is a simple and effective way to get in touch and send them relevant content. With The Radicati Group reporting that there are almost four billion email users worldwide, it is an infallible way to connect with your audience.

Let's look at an example of email marketing in action. Harvard Business Review Contributor Dorie Clark utilized email to boost profits and the email list of her consultant, all at the same time. She sent her subscribers a well-crafted email promoting the consultant's free teleseminar with in-depth descriptions about the consultant, his work and why her audience might be interested. This resulted in hundreds of new subscribers and $3,500 in commission.

It's a no-brainer that crafting the right kind of email matters to your subscribers as well as your business. It could be the push that nudges them toward a purchase or the shove that causes them to unsubscribe. Here are four mistakes that I have seen many professionals make when writing emails for their audience and how you can avoid making them, too.

1. A Generic Subject Line

Most people have a high influx of emails flooding their inboxes daily, many of which either get booted to the trash or never get opened. A likely reason could be that none of the subject lines caught their attention. Every email made them feel like they were just another number to the sender.

You can change how your subscribers feel about you contacting them, starting with the subject line. Brainstorm the message you're trying to send and come up with a relevant sentence or phrase that conveys that message in under 50 characters. Be careful when using all capital letters to get the recipient's attention -- this could just end up annoying them.

2. An Overly Formal Tone

There's a time and a place for formality, and your emails to subscribers are definitely not one of them. Unless you represent a tight-knit corporation, it's safe to assume that emails with a casual, conversational tone will get you the furthest. People love hearing from their favorite brands, and if you connect with your audience by showing them that they can see a friend in you, it will be easier to market to them effectively.

Don't be afraid to show personality in your emails. It goes without saying that staying professional is important, but the goal is not to seem like just another boring, generic brand reaching out to consumers. You want to come off friendly and personable so users feel comfortable and ready to hear what you have to say.

3. No Visual Content

People aren't reading the many emails sitting in their inboxes word by word like a romance novel. They're skimming them to see if they offer value. And if your email doesn't give them something new or exciting to chew on, you'll end up with another unsubscriber. That's where visual content comes in.

Including images, videos, screenshots, infographics and other types of visual mediums in your emails is a great way to break the monotony and freshen things up. Visual content also makes your email easy to skim and digest. This is key if your audience is going to enjoy reading your content. It will help keep their interest longer and, as a result, you'll see higher levels of engagement.

4. Spelling and Grammatical Errors

With all the advanced spell-check technology available these days, there's no reason why your business emails should have errors in them. They make your brand come off as unprofessional, immature and not credible. Unless typos are somehow part of your brand image, avoid them at all costs.

Turn on your email service's spellcheck and run it through a spell-check tool to catch what you may have missed. Read it out loud to yourself to make sure there's solid sentence structure and decent flow.

Over to You

Sending emails to your subscribers allows you to build robust relationships and retain customers. As its usage continues to grow year by year, its influence and ability to help grow your business only increases. Crafting professional emails is about knowing your audience and how they'd like to be spoken to. Once you figure that out, you'll be able to create emails that keep subscribers happy and keen on your business.

Jared Atchison is the co-founder of WPForms, a drag & drop form builder for WordPress that's being used on over 400,000 websites.