Hi Sanga,

1) Log into the database (using sqlplus) as a DBA user (you can use system/manager).

2) issue the statement:
CREATE USER name IDENTIFIED BY password
DEFAULT TABLESPACE tools
TEMPORARY TABLESPACE temp
quota 10m on tools;

3) Then grant whatever prviliges need to that user:
GRANT CONNECT TO name;
GRANT RESOURCE TO name;

hth,
Helmut