How do i need to study for the MCAT to improve my score?

i'm having a huge problem with the MCAT. i am not american and i live in syria so i don't think our universities are as prepared for the MCAT as are american schools. i have taken the test with a score of 8 in biological science and 8 in physical science. what do i need to do to improve my scores (although people with 8-8 in the mcat but with good GPA are getting in my country's med schools). do i need to practice with trials because i have heard that the MCAT can only be aced with practice, but then some other people tell me that doing trials doesn't help out much . i have 3 months to re-study. how many trials do i need to do and what should i do to make the whole experience more pleasant.