How can I increase my percentage of graduation which was pursued in 2005?

I have scored 40 % in B.com as i was pursuing other courses as well .As I want to apply for govt. jobs. I need 50 % so do I need to get admn in 3rd year directly or is there any other way out. Suggest if I can fill form now so that I can appear for exams this year or coming March- April session.