Mailing

"... after about 10 minutes of trial-and-error I realized I could beat the Gmail promotions tab in a few easy steps. By simply adding a personal greeting such as “Hi, “ making sure the email is sent from an account with a first and last name, and removing images, emails go straight to the “primary” inbox."

Zoranorak.com/land-emails-gmail-primary-tab-easily
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Rheti.com/beating-gmail-promotions-tab-hilariously-easy