Merge pull request #232 from nextcloud/jr-readme-instructions

Add instructions/caveats to README

README.md

@@ -1,4 +1,19 @@
 # Impersonate
 
 Allow administrators to become a different user by adding an impersonate action
-to the user list.
+to the user list. This is especially useful for debugging issues reported by users.
+
+To impersonate a user an administrator has to simply follow the following four steps:
+
+1. Login as administrator to Nextcloud.
+2. Open users administration interface.
+3. Select the impersonate button on the affected user.
+4. Confirm the impersonation.
+
+The administrator is then logged-in as the user, to switch back to the regular user account they simply have to press the logout button.
+
+## Note:
+
+* This app is _not_ compatible with instances that have encryption enabled.
+* While impersonate actions are logged, note that actions performed impersonated will be logged as the impersonated user.
+* Impersonating a user is only possible after their _first login_.