Update README

README

@@ -7,8 +7,15 @@
 Ansible playbooks of the University of Waterloo Computer Science Club.
 
 ** Usage **
+To run a playbook and request a user's ssh/sudo password:
 
-To run playbooks which require authentication as 'root':
+`ansible-playbook -kK -b test-playbook.yml`
 
-   1. kadmin -p sysadmin/admin
-   2. execute the ansible playbook
+To run a playbook as a different user (for example to provision a new system 
+that doesn't have sssd yet):
+
+`ansible-playbook -kK -b -u local_sysadmin test-playbook.yml`
+
+To run a playbook starting at a certain spot:
+
+`ansible-playbook -kK -b install-office-terminal.yml --start-at-task='enable magic sysrq'`