Testing in email marketing involves multiple elements, including:
1. Subject Line: Test different subject lines to see which one gets a higher open rate. 2. Content: Evaluate various copies, images, and calls-to-action (CTAs) for engagement. 3. Design and Layout: Ensure the design is responsive and looks good on mobile and desktop. 4. Links: Verify all hyperlinks and buttons are functioning correctly. 5. Sender Name and Email Address: Experiment with different sender names and addresses to see which ones are more trusted by your audience.