Some tried and tested “best practice” when you’re including images and video in your email campaigns:

• Always include Alt tags on images to manage blocked images issue
• Make images clickable
• Test rendering of emails to see if the email is still readable and actionable with images blocked
• Ensure emails include a "View as Web page" link at top of page
• Test video emails against HTML to determine which work best
• Balance video usage with short copy in email. People cannot view the video and read at the same time
• Do not use autoplay - let reader control the start, play, volume
• Include Call to Action (CTA) at end of video to drive people to click through