If you are using Lightning Experience console switch to classic console.
Go to Setup in the top-right section of page.
Now in the left pane, select Domain Management.
Select My Domain.
Choose your domain name, check for availability and if available, proceed by clicking the Register Domain button.
Test your domain once it is ready, by clicking the link and then click Deploy to Users.
Step 2: Configure salesforce as an identity provider
From the left pane, select Single Sign On (SSO) Settings from Security Controls.
Click on Edit for Single Sign-On (SSO) settings.
Now enable Federated Single Sign On (SSO) Using SAML in Single Sign-On Settings and Save settings.
In the SAML Single Sign On (SSO) Settings, select New from metadata file.
Navigate to your drupal site configurations Drupal SAML IDP Configuration IDP Metadata tab Download Identity Provider Metadata file.
Upload the metadata file downloaded in the last step and click on create:
Choose Appropriate Name, API NAME, enable Just-in-time user provisioning.
Download metadata file and note down login and logout url ( this will be required required to configure miniOrange IDP module as IDP )
Navigate to your drupal site configurations Drupal SAML IDP Configuration IDP Metadata tab Upload SP Metadata.
Check ACS URL and SAML Logout URL they must match the Login url, Logout url respectivelty from salesforce ( we have noted down these urls earlier ). If they don’t match edit them accordingly and click on save configuration.
Now click on the test configuration to test the connection.