How to execute this growth tip
Research: read the recommended readings and get a general idea of the guiding principles of subject line writing and testing. And write down all the ideas, don't worry about them being good or bad.
By this step you should have at least 10-20 subject line ideas you want to test with email campaign you're already running. Dive into your email software and make sure you have the ability to run an A/B test on subject lines. If you don't consider moving to a different platform. We recommend ActiveCampaign which is affordable, simple and lets you A/B test subject lines, email content, images, calls to action and more.
Pick an email that is already performing well for your A/B test. You always want to improve the top-performing campaigns first to get easy quick wins then work your way to the bottom performing emails. Set up your split test and run the campaign for at least seven days. Check your metrics (open rate, click-through rate, etc.) to see if they have improved. If they have a document why you think that is and move on to round two. Repeat until you can't improve the performance anymore (or until the gains improved are too small to warrant the effort).

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