Question

any advices and recommendations for maths olympiad??

Answer 1

yeah see the syllabus and start practicing practicing practicing and practice

Answer 2

hi mate

first of all best of luck for maths Olympiad.

let me begin by saying that to be successful in these olympiads you not only have to be good in maths but you have to love the subject in its entirety and appreciate the beauty behind it

Secondly and most commonly asked question is what kind of books to follow. Believe me lot of people will give a lot of suggestions as to which book to follow and most of them are actually right. But again it all depends on the student as to how much he may learn from those books.
Some which are recommended though are :

a) Problem Solving Strategies by Arthur Engel
b) Mathematical Olympiad Challenges (Publisher : Birkhauser)
c) Challenges and Thrills of Pre College Mathematics 
d) Elementary Number Theory (Jones)
e) Schaum’s Outline of Combinatorics
f) Problems in Plane Geometry by I.F.Sharygin (this book helps a lot)
and others