When you have finished the configuration steps and have completed a successful test, you can return to your subscription’s settings page and enable SSO. You can also wait and enable SSO later.
Once SSO is enabled, your team members will receive emails that include a link for them to follow that will allow them to connect their Overleaf account to their SSO identity in your IdP. If they are already logged in to Overleaf, they will see a notification in their Overleaf dashboard letting them know that they can now connect and log in with SSO.