First of all, log in to your Gmail account. Then, type your search criteria İNto the Gmail search bar.Then, you will see the red magnifying glass button. Click on it to build an e-mail list.Wait for GMass to build your e-mail list. Then, you will encounter a Gmail Compose window.Finally, compose your subject line. Then, type your message. Now, you may send the mail by clicking on the GMass button.