Hi Hassan,
Here are a few thoughts:
DifficultyThe main reasons why the exam is hard are:
1) Time limit - If I had another hour or so, I could have checked my answers and guessed on the questions I didn't attempt
2) Breadth - To be totally prepared, you really need to know just about everything you learned in undergrad, even though any given exam won't test you on everything
3) Multiple choice - This really kills me, because even though my reasoning could be correct, even one mistake in arithmetic, etc. will give you a wrong answer that will be among one of the 5 choices
Tips for taking the exam1) Get really fast and accurate on the computation-type questions. These are typically pre-calculus, calculus, differential equations and linear algebra problems. Doing this will give you a little more breathing room for more theoretical problems.
2) Don't get stuck on problems. If you can't see a way to solve a problem in 10 seconds or less, move on to the next one and come back to it at the end.
3) Memorize definitions and main theorems for abstract algebra, topology, real analysis, set theory
Obviously, there are many more things you can do to prepare yourself even better, but since the exam is less than 2 weeks away, you might want to focus your efforts a bit. Besides, if you're able to do the above, I'm guessing you should be able to do at least 2/3 of the questions correctly; assuming you don't guess on the rest, you'll be in the 77th percentile according to the most recent practice exam scoring guide.
Bonus tip: If you can eliminate even one of the answers on a question you don't know how to do, you'll be better off guessing because the expected number of points you'll get from that question is positive (see if you can work this out - it's good practice for the probability portion of the test).
Books1)
Cracking the GRE Mathematics Subject Test - This is a pretty good resource granted you know your stuff pretty well. If not, then it won't be so helpful.
2)
Mathematical Methods in the Physical Sciences - The smartest thing I did when prepping for the September test was working through the problems in this text. It's very short on proofs and gets right to computation and problem solving using mathematical techniques, which is great prep for the mGRE.
3)
Schaum's Outlines: Advanced Calculus - Good for practice problems in single and multivariable calculus and differential equations.
Hope that helps!