As everyone has said, its just about finding what suits you. I found chemistry tricky, until I came across the right study tools. For me, I start with watching instructional videos- a great example is (I think they do prelim but I'm not 100%) letslearnscience channel on youtube which breaks down the dot point in simple terms and helps understanding enormously! Taking down notes from that is useful, an I follow this by visiting sites such as easychem.com.au
be warned though, this is VERY basic and not enough detail is provided, but if it takes a while to wrap your head around some of the more difficult concepts, it helps. Because these are simplistic sites, for the addrd depth its a good idea to check out textbooks, particularly if you're not getting much from your teachers. Personally, I like conquering chemistry as it's not too overboard with the detail, but you are effectively covering the dot points.
Once you've got your notes it really is all about practice. Past papers, anything you can get your hands on really
Chem is something where asking questions is essential and group study sessions can help a well. As there's a large amount of content, splitting your notes into sections and cutting them down is effective. If you're a visual learner try flash cards, you get the benefit of writing them PLUS looking over them, so effectively you're doubling your study.
Good luck!!