When it comes to digital marketing, engagement-based email can be a gold mine for your company. The key is to look beyond the obvious when it comes to your subscriber base.

Simply checking to see who opens your targeted messages and who doesn't won't get you sales, but the following research-driven, richly targeted strategies can do the trick. Try these tips to boost your bottom line:

Use plain text emails.

A personalized message that is focused and doesn’t overwhelm your subscriber with too many product messages is a very effective way to garner their attention and prompt them to potentially buy from you. Also, plain text emails cut down on the graphics that can spawn spam.

Send your emails at the right time.

An analysis from Litmus found that 7% of email is opened between 7 a.m. and 10 a.m. While this is not a completely hard-and-fast rule, as email opening can be situational and fluid, it is a good guideline to time a new campaign with.

While emphasizing early email can be a great marketing move to increase engagement, don't pull back too radically on send-outs at other times of the day. That can garner you looks, too.

Sending a second evening email re-emphasizing points about a new product your consumer may have been introduced to at 7 a.m. could be a good way to cement the product in their minds.

Front-load, front-load, front-load.

Additional Litmus data also found that people spend an average of 13.4 seconds reading the average email. So, make sure your key message is the first thing they'll see, and make it sharp, convincing, and dynamic.

Stick to one clear, attention-grabbing concept at the top of your email, too. Cluttering things up with too many irrelevant details is a turn-off.

Be friendly.

Research from Ascend2 found that 23% of surveyed marketers found personalized messaging extremely effective. Don't overpersonalize by using the consumer's name too much, but make sure your copy is warm and inviting.

Speak to the consumer you're targeting in the same way you'd speak to a friend: it sounds hokey, but it works. Pull the consumer in with likability and immediacy before you emphasize the benefits of your goods and services.

Monitor consumers who haven't opened your emails.

If you see a pattern of this over an appropriate of time — say, 30 days — move your focus elsewhere. It's better to target consumers who are prompt when it comes to opening your email.

Even if they haven't bought from you yet, they're demonstrating interest and the seeds of brand loyalty. Mine their approval of your message by offering them clarity, respect and convenience!