f there’s one gripe dominating marketing, it’s Facebook’s latest algorithm shift. Facebook’s pivot to friends threatens to move brands and publishers even further down the news feed. As frustrating as it might be, it’s a good reminder that building an audience on other platforms isn’t really building an audience—not when those platforms can cut you off from it at any time.

That’s why it’s important to focus on channels that allow direct communication with your audience. Channels like email.

Email continues to quietly deliver results for publishers like the Seattle Times, where visitors from email “are 25 times more likely to convert” to a paid subscription than those from Facebook.” Or the New Yorker, whose strong newsletter program is practically raking up tote bags full of paid subscription dollars.

So when Facebook tweaks their algorithm, fight back with a little tweaking of your own. In your email program, that is.

Rigorous A/B testing ensures you’re getting the most from your email newsletters. Before the next Facebook announcement gets you down, get down to the Email Lab and experiment with an A/B test or two.

1. Test the subject line.

Running variations of a subject line is among the most popular email A/B tests, and for good reason. You can’t test the rest of your email if it never gets opened.

But don’t just change words just to change them. Figure out what subject lines resonate with your audience. That way, you might A/B test your way to a formula that works.

Publishers send a lot of newsletters, and many of them stick with the same subject line formula each send. These senders might fill in their subject line each day with a high-performing headline or a pun on the day’s top story.

Some publishers just stick with a generic newsletter name and date. It might seem redundant, but it also might be what works for you, especially if you have multiple newsletters. Axios does this with their weekly Media Trends newsletter, and they see a 50% open rate across all newsletters.

2. Use preheader text.

First of all, if you’re not using preheader text, you should try using preheader text! While not every email client displays it, enough clients do to make this a valuable piece of real estate. It’s like having a second subject line to play with.

Some emailers use the same preheader text each time. Others get a little more inventive, perhaps even using preheader text that plays off of what’s in the subject line. Whatever you test, it might be best to make sure it’s not critical to understanding your subject line because, again, not everyone will see it.

3. Think about your friendly from.

When your audience gets an email from you, what does the “from” line say? Typically email marketers use their brand name, an individual’s name, or a combination of the two.

Ever considered a friendly from A/B test?

In the Twitter age, many audiences are just as connected to individual writers as they are the publications they work for. If your audience has strong relationships with individuals, a person’s name (or their name, plus the publisher’s name) may result in more opens.

Whatever you do, don’t use a misleading name; the CAN-SPAM Act prohibits that.

4. Experiment with the length of your copy.

Do readers turn to your newsletters for concise headlines, or do they want a summary of the story before they click? Maybe they prefer to read the whole story within the email.

Try testing the length of copy to see what works best for your audience and the KPI’s you’re optimizing to. Some publishers use email newsletters to drive traffic to their site, while others prioritize building audience relationships and brand trust over clicks.

Above all, make sure your copywriting approach aligns with your newsletter’s goals.

5. Mix up the number of articles in your email.

Slate’s The Angle newsletter has 5 items everyday, while readers know exactly how many items to expect from the Top 10 newsletters at Axios. If you’re not locked into a set number of articles, you can see what changing the amount of items in your newsletter does to your newsletter metrics.

Will more links increase click-through rates because people are more likely to find links relevant to their interests? Or will longer emails overwhelm your audience, make their eyes glaze over, and eventually lead them to stop opening your newsletter? It depends on why audiences are opening your newsletter in the first place.

Either way, it can’t hurt to A/B test.

6. A/B test tweaks in your email newsletter voice.

Some brands are associated with a particular tone. Should you adhere to that tone in your newsletters, or does the email inbox give you space to kick back and write more informal copy?

Email is the closest thing to speaking directly to your audience, so a more relaxed tone can help some publishers strengthen ties with their audience. Still, don’t forget to read the room; test and see what resonates.

You can optimize subject lines and preheaders to your heart’s content, but it’s all for naught if your email’s contents turn audiences away. If you need help acting on the data in your email program, download PostUp’s “Achieve Email Strategy Nirvana with Smarter Data” solution guide to see how to get more from your data.

7. Get personal with personalization (or not).

Newsletters allow publishers to deliver relevant content directly to their audiences. Publishers can increase the relevance of each newsletter with personalized content.

The Austin American-Statesman experimented with sending a personalized newsletter, to great success. It saw triple the click rate of their normal midday send. PostUp’s Parse.ly integration allows publishers to do this with their own emails, populating newsletters with personalized content and even suppressing articles the user’s already read.

Still, another way to increase relevance and engagement is to offer multiple newsletters. That way, subscribers can self-personalize the content they receive, and publishers get additional chances to engage their reader. The average PostUp customer sees 3.12 newsletter subscriptions per individual, which means 3.12 chances to connect with each of them.

8. Shift your newsletter layout.

Overhauling your newsletter template layout might seem daunting, but if your newsletter isn’t working, the potential increased engagement might be worth it.

Of course, you don’t have to do something drastic. A template A/B test doesn’t have to pit a single-column layout against a two-column send. It could be as simple as a few quick shifts.

9. Check your use of images.

While you’re toying with template tests, think about your newsletter’s use of images. Do you use a single large image? Do you have a smaller image to accompany each headline? Will changing any of this increase subscriber engagement? Try it and see.

Just don’t get too carried away with images. Heavy image use can increase loading times, and plenty of people don’t even load images at all.

10. Change your sending time.

Many publishers send news digests early in the morning or during the evening. Will more people open your newsletter if it comes when they’re not busy, or will you benefit from being top-of-the-inbox at another time of day?

It depends on your audience.

For example, while Vox normally sends their popular Sentences newsletter in the evenings, they have occasionally tested 6 a.m. sends. Vox found that evening sends performed better; however, that might be unique to their email list. Their subscribers signed up for an evening newsletter, and they expect it to arrive in the evening.

It’s possible that some of those people would actually prefer a morning newsletter. Publishers like Politico send AM and PM versions of their flagship newsletters, which could be another thing you test.

Publishers are increasing their email output all the time.  Among others, The New York Times and Washington Post offer dozens of newsletters because (like The Seattle Times and The New Yorker found) its ability to engage and convert subscribers can’t be beat.

Whatever newsletters you add to your email arsenal, just make sure you keep testing.