There is no shortcut to clear any exam..Only thing you need to do is Reading, I suggested you the good books.
Read daily newspapers. For Library Science simply read above said any one books and it will be enough.
Allot Time, Read, Revise, Attend Mock tests.
All the very best.
For the post of Librarian,
Part I will consist of 40 multiple choice questions in the subjects English and Hindi carrying 1 mark each.
Part II will consist of 160 multiple choice questions carrying 1 mark each comprising of Current Affairs (30),
Reasoning and Numerical Ability (30) and
concerned subject (100) questions.