Do these steps to create a rule in Google Workspace:

1. Open the google admin console.
2. Go to apps apps -> Google workspace -> Gmail -> compliance.
3. Click on CONFIGURE next to content compliance.
4. Under Content compliance fill in Zivver: Secure message by sender.
5. At 1. Email messages to affect choose Outbound.
6. At 2. Add expressions that describe the content that you want to search for in each message choose:
   1. If ANY of the following match the message.
   2. Click on the Add link.
   3. In the drop down menu choose Advanced content match.
   4. Choose Subject for Location.
   5. Choose contains text for Match type.
   6. Choose a word which you would like to use in the subject to send secure emails (e.g. Encrypt or Secure email).
      
   7. Click SAVE.
7. Under 3. If the above expressions match, do the following > Route, select Change the route.
8. In the dropdown change Normal routing to Zivver Send Connector.
9. Click SAVE.