Before you send a test message:

Details tab: 

• The right subject line? 
• Appropriate From Name?
• The right From Address? 
• The right Reply-to Address?
• The correct CAN-SPAM footer?

HTML or Message Builder tab:     

• Preheader?
• Any Lorem Ipsom/Anecdotes? 
• Call-to-Action?

Link Tracking tab:

• Any warnings? 
• Selected the right links to track?

Preview/Send tab:

• Review in the browser to assure it still renders as you remembered.
• Inbox Preview - review how your mailing renders at different inboxes in both light and dark mode. You are also able to view the Images off and on to view how your alt text renders. 
• Send a test to any and all that need to review. 

Now you have that email…..what should I do? 

• Preheader - adjust the size of your window to see how different-sized windows will affect the wording of your PreHeader
• Personalization/Dynamic Content - does it all render correctly? 
• Links - Does every link work, clear your browser history, do they still work? 

PRO TIP:  Evaluate how Images look in a thread and how they render for someone who marks your email as not spam and moves it to the Inbox.