Instructions tab in Mail merge
4. To start writing your email, just click on the second tab, labeled Email text . If you want to add custom fields in addition to the first and present names, just add double brackets << like this >> and make sure you spell the same fields in the same way when using it.
Compose an email.
5. Next, switch to the third tab, Data to be merged , to add email addresses and other information. If you've added a new custom field like the one above, you'll need to enter them in the net above. Import or paste data into a spreadsheet.
Merge data.
6. To see if it works, select Test Mail Merge from the Mail Merge menu (if not visible, try reloading the page).
This returns the first 3 messages as a test if merge works. You will need to authorize the scripts the first time you use.
7. If everything works fine, you can now choose Run Mail Merge from the Mail Merge menu so that the script does its magic. Good luck!