Create User Certificates via Apple Keychain

1. Open “Keychain Access“.
2. Select “Certificate Assistant“ > “Request a Certificate From A Certificate Authority“.
   
3. Define “Name” and “Email” for the user.
4. Select “Save to disk”.
5. Click “Continue”.
6. Select “Keychain Access“ > “Certificate Assistant“ > “Create Certificate For Someone Else as a Certificate Authority“.
   
7. Drag the request created before.
   
8. Select your CA created before.