U can improve by firstly understanding the book really well. Read the textbook and A+ notes a lot as it is a really good resources to use for. Also the tsfx notes are great too..they always go beyond the content for some reason but the notes contained basically cover everything u have to know before the exam.. As for how to improve on applications, try to highlight the important words after reading through the question(e.g. explain, outline..). If u still dont understand it, try to read a few more times and then give it a best shot. If u feel like u can't answer the question, go back to the relevant section in the textbook and revise and maybe watch some animation if required. Try to fully understand the contents rather than rushing to do exam papers. This will just lead to anxiety and confusion! Good luck

Try to do some easy test paper like Lisachem, STAV(have really good and understandable question) rather than going those VCAA, NEAP...