Continuous classroom is very helpful. but the more hands on experience you have, the better. You will want to have a good understandingon how to deal with different scenarios from different platforms. Desktop vs. Enterprise mostly. You will want to have a good handle on how to use expressions in chart objects, understand set analysis very well and know what the limitations of Qlik Sense are and when you need to develop or seek out custom objects.
Although this may sound very vague, a.) the questions are super detailed so it's difficult to give more detail regarding them and b.) you are asked not to share specifics of the exam. But the framework above is a good supplement to this which is posted on Qlik's certification page (link below). The exam domain drop down is a good place to start. Structure your studying on that framework and just know the UI inside and out. Good luck!