I am glad that I scored 7 overall for my first ielts exam. My listening was the highest which was 8. There is no clue how you catch the answers, the only way is to concentrate on those speakers and practice more with past papers as you can get used to their speed and structural of questions. For reading, you just have to know certain amount of vocabulary, at least you will be able to understand what the task is about. The way I did in the exam was to skim read the task, this is because there must be a lack of time if you are trying to scan read the tasks. Also, there are only some paragraphs contain the information which you need to answer the questions. I found writing the most difficult. you need to have writing skills to get reasonable good marks.
Speaking was not that hard at all, be confident in the exam, speak fluently that would give you most of the marks. In my point of view, the most efficient and effective way to score a high mark in the ielts, is to keep practicing whether reading, writing, listening or speaking and also read loads of English books and CDs. Anyway, the more practice, the more confident you are while you are in the exam room. Good luck guys!