There are a lot of similar topics here. And there are a lot of online resources offering materials for preparations, along with tips, techniques and stuff like that.
Thus, I'll provide a summary of my personal experience:
1. Your initial English skills must be taken into account when planning out your personal preparation plan. I was quite confident and didn't want to waste more than four weeks on preparation, just while my educational credentials were being prepared and assessed by WES. But remember, one month is enough to cover all four skills in terms of getting acquainted with corresponding exam parts and sections, types of tasks, major strategies and techniques. It is absolutely not enough to actually improve your English but to work on your exam skills.
2. I decided to attend an intense preparation coarse which lasted exactly four weeks (3 classes a week) with interim sample test. And I can tell ya it was a very good investment as I was provided with all the tips and tricks I needed, including all standard letter openings and endings, types of essays, approaches to cope with all kinds of listening/reading and speaking tasks.
3. Do not waste your time on the academic module tests. Look for sufficient amount of General module training materials and sample tests.
4. During listening part of the exam don't hesitate to put comments with your pencil even in your native language. It is vital to grasp the main idea, numbers and names and if you waste time on proper spelling you will most likely miss the next question. However, it is important to double-check your spelling when transferring your answers to the answers sheet.
5. When preparing for the speaking part, train to speak about yourself, your job, your childhood and stuff like that in short but nice and grammatically correct phrases. Use less common lexis. Ask your friend to throw stupid question in you so that you would have to provide a fast response even though you have no idea what to talk about. It's a very useful skill to speak on any topic starting with various openings, reasoning and discussing situations and phenomena your are not familiar with. You can be asked really unexpected and sometimes silly questions but there would be no time for frustration-contemplation
Be calm, smile and keep saying something.
6. There's a sound check before your listening part starts. Feel free to ask them to reduce/increase the volume.
7. During listening part there will be some time given to check your answers between sections. Use it to take a look at the next couple of questions so that you will catch the overall idea and know what to expect.
8. In the writing part, do not be afraid to spend a couple of minutes reading the task, instructions provided and understanding every word of it. It is crucial to digest the task and bear in mind what's your goal and what's expected of you. Once you know all the standard types of writing tasks it will be a cake walk for you.
There are a lot of other tips you can find online. Search for IELTS 101 useful hints just to start with. Then google for more.
