First of all , Get a copy of previous year question papers if possible with solutions. Having a hard copy is very important and we are going to refer it again and again during whole preparation....Refer to syllabus and analyze the number of questions asked in each subject. As all subjects don’t have equal marks, few subjects are preferred over others. I mean few subject may have more questions asked in exam than others. ..Make a priority list of subjects based on marks or preference given it in previous exams.