add new rt admin user creation procedure

howto/rt.md

@@ -274,6 +274,16 @@ The support help desk coordinator needs the following assets to perform their du
  * `root` password for Request Tracker.
  * Being owner of the “Tor Support” component in Trac.
 
+## New RT admin
+
+This task is typically done by TPA, but can technically be done by any
+RT admin.
+
+ 1. find the RT admin password in `hosts-extra-info` in the TPA password
+    manager and login as root OR login as your normal RT admin user
+
+ 2. create an account member of `rt-admin`
+
 ## Pager playbook
 
 ### Ticket creation failed / No permission to create tickets in the queue