Hey! For our class, we have this textbook called 'Topographic Mapping for Secondary Students' and it contains a bunch of different maps with skills based questions, so if you guys have that, I really recommend using it. Also if your school library has the excel textbook for Geography, i recommend using that as well.
For more complex skills such as interpreting ternary graphs and reading logarithmic/semilogarithmic graphs, I watched youtube videos to help me understand them, and then looked up a few examples of them on the internet and just practised looking at them. You could maybe even find an (older) HSC past paper and just practice the multiple choice skills questions in it. Just keep doing skills questions until you get most of them right (kinda like maths).
http://www.geographyskills.hsieteachers.com/stage-6.html This website has some explanation and a few practice questions on a few of the skills. I found it really helpful for learning how to calculate the gradient of the slope as a ratio and calculating vertical exaggeration.
Hope this helped a bit and good luck on your exam!
