Once upon a time, in a world pre-Instagram, iPhones, and a married George Clooney (we're talking 2006, people), marketers and business owners alike opined the demise of email marketing. There was just too damn much of it, they said. Find another way to reach your audience, they cautioned.

The advantage of hindsight is that we can see the issue wasn't so much the volume… it was the access. Back in the old days, people had to sit down at their desktops or laptops to check their email. Not an easy thing to do from a Jamaican beach or a cozy bed or while waiting in the carpool lane for the kiddos.

As a result, email annoyed the masses. Just stop, we all thought. PLEASE.

But then a funny thing happened: the dawn of the smartphone era brought with it a new appreciation for email. Or, at least, a grudging acceptance that it was here to stay, thanks to the fact we could now easily check messages wherever we roamed, be it the movies, the soccer field, even the toilet.

To wit, as of today, 66% of emails are opened on mobile devices. And people aren't just opening them but acting on them as well. In other words, email marketing's got game. And if you want to play, you need to update your skills, strategies, and moves.

Which brings us to this happy little blog post. We've compiled a list of insightful, instructive, and current email marketing tips that'll help your campaigns kick butt in 2015.

So let's get to it.

Defining your email marketing strategy.

We like what Vertical Response has to say in this article: 4 Tips to Refresh Your Email Marketing Strategy. The steps cover the biggies, especially the importance of making sure your emails are mobile friendly. We especially love this tip:

"Along with responsive design, we recommend using a serif font (those with legs or tails) for your headlines and sans serif fonts for any other text. These are easiest to read on a computer screen. Use font sizes between 12-22pt to make sure your email is readable. Headlines can be 22pt, additional font in the email can be 12 pt or more."

And, of course, make sure you're up to speed on the latest buzzword: contextual email marketing. Get Elastic gives the scoop in its article, Age of the Real-time Inbox.

Growing your newsletter list.

Let's face it. The best emails in the world won't do you any good if you don't have a solid list, one you're constantly growing. The folks at Constant Contact recently published 15 creative ideas to grow your email list. Tip #9 is one many businesses overlook: "Make it convenient for customers to join your email list by giving them the option to sign up with their mobile device." Constant Contact then outlines two ways you can do this.

Need more inspiration? Check out these five actionable tips for growth hacking your email list (brought to you by the smart people at Impact Branding & Design).

Avoiding mistakes.

There's no limit to the number of "mistakes" articles on the Internet. Here are three that are worth checking out:

Learning from the best.

And that's not hyperbole, either. This interview is with the recipient of the 2015 Stefan Pollard Email Marketer of the Year Award, Alessandra Souers. One of her power tips to email marketers? Learn Photoshop. "I think it’s important to be really self-sufficient as an email marketer so I think Photoshop really is important."

Getting into the nitty-gritty.

We always turn to HubSpot when we're on the hunt for detailed "how to" guides. HubSpot doesn't disappoint with these titles:

Knowing where to go when you need help.

Hi, there! <waves hands furiously> We can help! At PMG, we have a long history in developing email marketing campaigns, calendars, templates, tests, and lists that get our clients results. Let's talk

And long live email marketing!

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