For sure you can prepare the test on your own, but the sticking point is how many months would you like to pass. Accordingly, that is a matter of "TIME" which is the most influential factor in many of language tests. Once in a while, time can be bought by money in this case. With good English teachers with excellent experience, they would make you spare a plenty of time to overcome at a comparatively low cost including money and effort. That is why in most cases, candidates had better need eligible teachers to conquer the test and please bear it mind that time is the money which is very true in this case, especially in the very first beginning when you have no idea what IELTs is.
I would recommend you to get an online teacher who has experience with IELTS preparation. Or possibly a preparation class near you, if there is one.
I prepared myself for IELTS Academic with the overpriced "official" preparation material, plus free online resources. And I ended up scoring much lower in the active skills of writing and speaking than in the passive ones. I am sure I had more potential there, but wasn't able to unfold it with solo preparation.