well obviously i’d recommend doing all the past hsc papers, since there’s about 20 or so papers on nesa’s website and the paper each year is pretty similar to those tbh.
for the long response type questions, you should already be really comfortable the stuff about development methods (agile, structured etc) and have it memorised since that’s usually 5-10 marks of the paper, just arguing how one of the methods is applicable to a situation (fyi usually there are 2-3 valid options, it’s just about how you argue it). same with the software development cycle, you should know all those key terms in all the stages eg how to make maintainence easier, what tools/diagrams can be used in the planning stage etc, that’s another 5-10 marks of the paper that you should be getting pretty free if you know the cycle well. similar for the ethics type questions, compiler stuff, fetch decode execute reset, probably more that i forgot, it basically comes down to common sense and memorising the key stuff
for the other longer response questions, that aren’t as formulaic, i’d really recommend always linking stuff back to the scenario they give you. eg one question they asked about how using a pilot approach would be beneficial for a study tracker app, don’t just give a generic answer like “can help with minimising errors”, that might get you full marks but it’s safer to write something like “students can help identify errors and bugs, allowing for the final product to have less issues on release” so literally just bringing in the key terms in the question. besides that, if you can’t think of anything substantial just try to use common sense in those situations. eg if they ask about why structure charts can help in planning a piece of software, and you forget specifics about structure charts, then just think about how it would help you if you were building a project. pretty much through common sense you can deduce that it would help as it would provide an outline of how different modules interact with each other (since that’s literally what a structure chart is) and so it would help in planning how different parts of the software interact with each other. that’s a simple example but in this subject if you ever get stuck, you can at least get a few marks or even full by writing down pretty simple stuff like that lol.
for multiple choice there’s not really anyway to prepare besides memorising all your notes and doing all the hsc papers, just make sure you know all the little quirks in the syllabus like rules about dfds and stuff. similar for algorithms, id say if you’re really comfortable with the stuff they ask in hsc, you’re probably fine. again if you can’t think of something, at least write down a sketch of how you think it will work, that’s still at least 1-2 marks you’ll get for the question
i can’t comment on the paradigms topic but for the interrelationship one, definetly make sure you know the ascii characters for a and A, how to do all the conversions, how to deal with complicated truth tables and boolean algebra (sums of products etc), and also try to understand at a binary/hardware level why stuff is, eg why overflow bits happen, why does 2s complement work well but 1s complement doesn’t, etc. again if you do all the hsc papers you should be fairly prepared for the topic tbh. so my main advice is really just to do all those lmao, i did them like 3 or more times throughout the hsc year tbh