Personalisation in the subject line, Short subject lines and A/B testing to identify the best time to send them
yes
Keep the subject relevent and engaging.
Design the email for impact, make sure there is a CTA. Think what would success look like? Hopefully, the answer isn’t simply the reader read it, but that they took a measurable step toward becoming a customer.
Use preview text to create intrigue and drive opens. Don’t skip testing - especially CTAs and cross-device.
Aside from personalization, keeping your message clear and concise is important to keep your readers attention. If things get too “wordy” people can potentially lose focus on the main message and completely miss the call to action. In addition, making your main points stand out in the email by using bold lettering or a different color than the main body text can help to increase your clickthrough rates.
I’d like to have A/B testing option, but it does not include in our plan. But I always pay attention to CTA, Subject LIne
member
Personalization by personna is great, as is keeping the body of the email consise with engaging visuals and a clear CTA
Make sure you know your audience!
Personalize it and keep it simple and precise! 
use a relanvent subject line
Making message clear
personalisation goes a long way!
For B2B companies, segmentation certainly helps as different industries may be more responsive than others and offer relevant content. Having complete records with their name and company goes a long way than getting an email that says, “Hi there.”
Good info
Know your audience, talk to your customers to understand the importance of their position in their business. We did an exercise of talking to the back office of an organization and got an open rate of 86%. Yes, personalization is more than just their first name. A consistent tone and voice should be reflective of the brand.
I like to use subjectline.com to make sure my subject line is optimized and useful. Then I make sure the message iteslf is enticing and valuable to my prospect. I am a big believer in segmenting my lists to make sure I am sending the right message to the right person.
I have found the best performing emails are ones that cut out the jargon/schpeal and get to the point of ‘what’s in it for you’ - as well as providing just one clear CTA (which is hyperlinked on images and at least once elsewhere in the email)