Use the following code to create a simple user:
CREATE USER nista IDENTIFIED BY kookoo;
GRANT "CONNECT" TO nista;
--optional:
ALTER USER nista DEFAULT TABLESPACE "USERS" QUOTA UNLIMITED ON "USERS";
GRANT "SSE_ROLE" TO nista;--for Siebel
GRANT SELECT ON APPS.MY_TABLE TO nista; --for any object, here table
GRANT SELECT ANY TABLE TO nista;
GRANT CREATE ANY PROCEDURE TO nista;