So, email turned 45 in 2016.

It’s an impressive age for a marketing tool in the digital era, and every few years, email is proclaimed dead, over, outdated, only for boomers, or facing a sharp demise in the near future. So far, the naysayers have been wrong. Email is only getting better with age—73% of B2B marketers surveyed by Salesforce in 2015 said email is essential to growing their business.

However, with age comes a complexity that we all have to keep up with. And if you’re anything like me, the amount of valuable information available about successful email marketing is inversely proportional to the amount of time you have to read, absorb, and reflect on it.

If email is a key part of your marketing mix, fret not. We went to Content Marketing World to bring you this year’s hot takeaways. (You’re welcome!) And the first four-and-a-half points come courtesy of Jessica Best (@bestofjess), Director of Data-Driven Marketing at Barkley.

Point One: Avoid the Internet Black Hole

A whopping 30% of valid email in the U.S. (i.e., sent to a working email address) never makes it to the inbox in question. This is the kind of figure that scares the tuna salad out of hard-working B2B marketers with tough performance goals. It’s difficult enough to convert prospects who get your emails, but when they don’t…

The good news is you’re not powerless. You can measure your company’s sender reputation (we all have one, realize it or not) at senderscore.org, and then deal with any hard bounces, complaints, spam traps, or blacklists hurting your inbox reach. Email data solutions provider Return Path has good resources on this.

Point Two: Fix the Hidden Money Pit

Is your email list antiseptically clean? Then skip this section.

If you’re in the muck with the rest of us, approximately 40% of people on your email list haven’t opened, clicked, or taken an action in over a year. In other words, they’re inactive. And inactives drag down your metrics—200 opens from a list of 1,000 is 20%, but if 400 of those email addresses are inactives and you cut them, your 200 opens would represent an open rate of 33%. Bonus for you!

Inactives also increase your send cost. Trim them or, if you have the patience, try to re-activate them with special offers, exclusive access, state secrets, or anything else desirable that’s rattling around your office.

Point Three: Keep Testing

Don’t be fooled by blog posts claiming there’s such a thing as magic words or phrases for email headlines. The wording that compels the engineering director of an enterprise technology company to click won’t work for a channel partner targeting SMBs. In other words, if you want your email programs to yield results, you should develop an obsession with subject line testing.

Perhaps your statistical analysis skills are a bit rusty? Then make sure your A/B tests are statistically significant here. And stop by WhichTestWon on a regular basis for inspiration—and to remind yourself that there’s often no discernible logic to headline success.

Point Four: Prove Email’s Value

Calculate your email ROI. Not sure how? Of course you are. You were first in your advanced calc class, right? But for those of your friends who weren’t, there’s the calculator at EmailMarketingROI.

Point Four-and-a-Half

Live in fear of the spam button.

I’m going to let that one speak for itself. The final point, we picked up from Mathew Sweezey of Salesforce (@msweezey).

Point Five: Write Like a Human

OK, you knew that. But be honest. Every B2B marketer needs to be hit over the head with this one on a regular basis. If your conscience is clear, send this to people in your network who write rambling announcements of product launches in passive language without a hint of what’s in it for the reader.

First, people only read 20% of any promotional email,* so why do we keep writing the other 80%? When the urge comes over you to add another paragraph about the award your company won, think of Elmore Leonard, who said, “When you write, try to leave out all the parts readers skip.” True for fiction, truer still for email.

Second, we all know you didn’t write the slickly designed email that ends with your digital signature. It’s not from a fellow human, so why should we bother to look at it, let alone respond? You don’t need to write all email personally, no. But save the fancy design for your newsletter and honest-to-God auto responses, and skip it in your email marketing. Use text to sign your name, not an image.

*The good Mr. Sweezey didn’t share his source for this stat, but I choose to believe him because it sounds right. And yes, I’m familiar with the concept of confirmation bias.