OK. We'll try this again.
If the real question is more in the nature of "What tasks do I have to do to create a userid?" (and your userid has the appropriate permissions)
- Use the ADDUSER command to add the user to the RACF database/
- Use the ADDDSD command to create a userid.* profile in the RACF database.
- Use the DEFINE ALIAS(NAME(userid) RELATE(user-catalog name)) command to create the user alias in the master catalog to a user catalog.
- Most sites have additional requirements; you'll have to find out about them on your own. The first three are essentially universal. The last time I did this I think there were 10 things I had to do.
If the real question really is the topic; with RACF it might be recorded in SMF, but I rather doubt that's the answer you want. I know the more recent Top Secret releases store this information in access permissions; I don't know about user definition.