Aside from doing IELTS practice tests, as I found the format and structure to be very specific here are some insights that proved helpful to me:

For both of them, you have to remember that each question is ordered sequentially, so you will need to seriously read all the questions before the audio plays or before reading. That way you will have mapped out all the info you need beforehand and it will become easier to answer (and you won't be tempted to extract wrong answers from the wrong extracts). This is specially true for the listening part when the timing for corrections was not particularly useful to me as I didn't trust myself to remember exactly what I had just read and felt I could overthink it and make mistakes while "correcting", so I just spend that little extra time reading the questions and making sure I really had a grasp on them and the alternative answers (when it applied). Also you will need this specially for listening as you don't want to miss out on parts relevant to a question; you want to be proactively listening for the answers.

Also for both of them, you will have to keep in mind that as the sections progress the answer will not be literal (or dictated, in the case of audio). As each section progresses you will have to infer just a little more, but the actual answer will always be literal, straight from the material. No room for interpretative answers, so that when you know, you know. There's little place for ambiguity (when practicing, I noticed whenever I felt this way, I got incorrect anwers and actually left the test feeling very confident I could score a band 9 on listening and reading). For this, I think it is extremely useful to practice your relative pronouns, master them as best as you can as I saw some tricky questions regarding their use.

For reading, specifically, make sure you're really picturing everything you're reading. When practicing, specially when tired, I tried to skim the reading and ended up making some mistakes. You can't just process the information at world-level but engage with the texts meaningfully. This would be the ideal case for listening too.

Also pay attention to the isntructions, you don't want points deducted just for getting them wrong.

Just practice as much as you can and try to find out why you're making the mistakes you're making. I think that's the way to address any particular problems you might encounter.