There are plenty of online resources which will help you prepare for the test. Be prepared and get yourself familiar with the different styles of tasks (IELTS use a variety). Googling it does the trick. Also, Anne is right ---listen, read, write, and speak the language on a regular basis. Though, you just need Speaking and listening results, you would still need to complete the other two components. There are agents (review centres) who offer you a free mock test if you opt to register with the BC through them. I am sure you will do well.
The good thing about taking IELTS is, if you reach 4.0 for both listening and speaking, you will be able to use that same certificate to apply for ILR (provided immigration laws do not change) as 4.0 is already B1. Hence, saving money time and effort in the future.
Good luck.