After I instaled PostgreSQL on Amazon Linux AMI, first thing after database server was up and running I start thinking how to create user with administrative privileges, so I can access it using some management applications.

So, here is how to create superuser and set password, which will allow to access PostgreSQL using admin tools.

[root@ip-10-8-1-1 data]# su - postgres
-bash-4.1$ createuser pgadmin
Shall the new role be a superuser? (y/n) y
-bash-4.1$ psql
psql (9.1.5) Type "help" for help.
postgres=# ALTER USER pgadmin WITH PASSWORD 'pwdaccess'; ALTER ROLE
postgres=# \q

And now I can use pgadmin username with password pwdaccess to connect to PostgreSQL instance with management tools (for example pgAdmin3).