tuning

 Please suggest on below data for the improvement of database performance. Also suggest how to read this data and how we should approach for db tuning based on below output.

MAJOR    MINOR         WAIT_EVENT                                      SECONDS    PCT
-------- ------------- ---------------------------------------- -------------- ------
CPU time parsing       n/a                                               27788   .00%
         reloads       n/a                                                5499   .00%
         execution     n/a                                            25839758   .00%

disk I/O normal I/O    db file sequential read                     67001073999  8.95%
         full scans    db file scattered read                      82626892427 11.04%
         direct I/O    direct path read                            31828454341  4.25%
                       direct path read temp                        2519375619   .34%
                       direct path write temp                         63988123   .01%
                       direct path write                               3420061   .00%
                       direct path sync                                1577328   .00%

MAJOR    MINOR         WAIT_EVENT                                      SECONDS    PCT
-------- ------------- ---------------------------------------- -------------- ------
disk I/O other I/O     control file sequential read                 1703936850   .23%