A question I often get asked by my IELTS students is, 'When can I take my test?'  This obviously depends on what your current score is and what score you need.  My advice first of all, is to take a course in IELTS, and when you are getting the score you need, consistently, in every mock test that you do, then you are probably ready.  To be sure, for example, if you need to get 6.5, then in a mock test you need to be getting at least 6.5.  If you get higher than this then you should definitely book your test as soon as you can.

Another factor to think about is, why you need to score.  Maybe students take IELTS to gain access to university.  So you need to be getting your desired score with enough time before the start of your university course so that if you don't get the result first time, you will still have time to re-take the test.  You must achieve the neccessary results before you start your course.

When you feel you are ready, you need to contact the IELTS test centre directly.  I used to advise contacting the centre to enrol for the test at least one month in advance.  Now, however, I advise you to contact the centre about 2 months in advance, because spaces on the test get booked up very quickly.  this is because in recent years IELTS has become more and more popular.  Well, it is the best English language exam.  Call the centre and ask if there are any spaces available on the date you wish to attend.  If they say, 'Yes'  then ask them for an application form.  Fill in the application form and send it off.  With your application form you may need to send signed passport photographs to confirm your identity when you get to the test centre (remember to bring your passport on the day.  You will also need to send the fees for the test.  Aks the centre how much these are and send a postal order with your application form.

You can get information on test centres around the world from www.ielts.org For example, if you live in London, you can visit

http://www.ielts.org/test_centre_search/search_results.aspx?TestCentreSearchSubRegion=01502ae9-cf4b-46ba-8214-c5d4331a543d

and you can see which centres there are and when the next available date for the test is.

Good luck with the test.