Using DBMS_Profiler or other techniques for procedure profiling - oracle11g

Hi,
    I have a stored procedure which is quite huge.
It gives results but it tends to take some time.
I am trying to see if I can profile it. I have never done this profiling for tuning before.
Can someone explain me how I can profile the procedure?
I want to see which block in the procedure plsql, its taking time..

currently, I used like below:
storedprocedure()
variables....
x integer;
begin
x:=dbms_profiler.start_profiler('Test Profiler');

stored procedure plsql code..

x:=dbms_profiler.flush_data;
x:=dbms_profiler.stop_profiler;
end;
/

After using like this, I am having difficulty how to approach further.. after executing the procedure..


Thanks
Aeddy.