I am offered a place at Cambridge under the condition that I pass IELTS with a 7.0 out of 9.0 score on each part (reading, listening, writing, speaking). I have studied three years on a college in the Netherlands where the instructional language is English. I write papers in English and I feel like the language I use in those papers is quite good and mature. However I still find speaking English a bit unnatural. I want to know how hard IELTS is and whether or not I should study a lot for it. I know that I should get myself acquainted to the way they ask questions, this is not what I mean with studying.
On the internet I found no really useful information on how hard this test is. I am really in the dark here (also I am also quite confident that in principle after three years of studying in English I should be able to cope with the required level).