It seems like there is a large disconnect between your scores, which is actually more common than you might think. To me the large fall off comes from lack of confidence in the material. There is no reason that you should have such a large drop off. Here are a couple things to say to get the conversation going:

1) SC - Focus on the differences between answer choices. Decide which variation is correct based on sentence structure. You can look at the beginning of the underline, end of the underline and at punctuation to find some of the errors.

2) RC - Read for structure. You are going to have to go back to the passage to answer most questions, so try to paraphrase as you read the first time and use your map to help you locate detailed information in the question.

3) CR - Ask yourself, why is this answer wrong? Eventually select the least wrong answer. This helps you from jumping to conclusions.

Should be a a decent start...

Hello,

You are lucky because even if your last score was not as good the previous ones, all your others tests were very high. I sat the gmat this morning and got 530 with two previous mock gmat before: 530 and 510.
I seriously think that I am doomed because I sat the French Gmat last year and had 280/600 which is not that good too. Every time I worked 4 month for each exam. I am a serious worker and not a stupid person but I really have the imrpession that I do not have the adapted reasoning for the Gmat...
So if you have any advice that would make my brain click to gmat thinking I would be happy to know them!