Go to Automations → Message Opt-ins
Select Add opt-in. A window will open
Name your opt-in
Add placeholder as the Opt-in Trigger (don’t worry, we’ll fill this out later in Journeys…see, weird 😉)
Select Save & Next
On the next screen, select the grey rectangle on the left. Then Save & Next (leave blank)
Now select the grey rectangle on the right. Then Save & Next (leave blank)
On the Opt-out page, add your opt-out keywords like STOP
Now we need to add a blank template by selecting Create Template → clicking through to Save (we’ll cover this with a Global opt-out flow):
On the final page, select Finish