12th Board...What should be strategy..?

Hi....all there
Today i had my first day in class 12th.
As I expected every single teacher started. It's Not easy this tym..................Work hard , don't play, keep your notebooks complete this tym(I prefer not to make notebooks)and everyone warned me to not to bunk classes....................!!! nd blah blah blah!!!!!

I'm not so great in studies and not even so dull..... bt yes i really want to do something good this time at least 75% in my 12th.

Guys Plz share what should be d strategy........How can i enjoy as well as get good marks.......