Hmm You can't make yourself like studying , but maybe can try
studying smart.
What i did for my "O"s is I set aside blocks of subjects ie,
tomorrow must study at at least 3 hrs in those 3 hrs must study
social studies , maths chinese.
Then i arrange the schedule the rest of the day to make sure that
the longest i study at 1 shot is 1 hr.
In this way , you won't get tired from studying all at 1 shot and
can concentrate better , its the quality and not the quantity that
counts.
My typical schedule went something like this :
Monday
900 TV
1000 Social Studies
1100 Computer Game
1200 Maths
etc etc
Try it 
though its rather unconventional ,
it works
