Hey there,
Hermansia who achieved a band 6 has written her top tips to gaining a band 6 which you can find here
Although I'm sure many other people would be willing to share their top tips to ace economics even though they may not have gotten a band 6 (results are still yet to be released)
Good luck 
Man those are good

Thought I'd give another two cents worth as well though, maybe you'll find these helpful too.
For me, something you can be doing throughout the year is looking at articles, and taking down notes - maybe do one article a week and find statistics. (This is something I didn't do, but wish I did!!) In this way you can kind of build up a bank of relevant statistics which are real important in essays.
That said, the best way for me to learn content was by practicing short answer questions. Because short-answer questions make up 40 marks (and multis make up 20), it's important that you know your content in a way that you can maximise marks here. So after you've kind of looked over your notes, think about how you would answer shorts on these topics. One GREAT way of doing this (and something that helped me very much) was doing it within the context of a study group.
Get together some of your mates and just talk about economics, I went through the entire eco syllabus with a mate the two days before trials and just talked over each dot point (and ended up topping alongside him). I can't underestimate the importance of collaborative learning in eco, especially because the whole course is based on relationships and explaining it to one another helps to consolidate your understanding.
Another thing I wish I did for HSC (but could be unrealistic) is create an essay plan bank - kind of like the way you collect statistics, but for essay plans. This is a really efficient way of condensing content and statistics into one place and would really help you in trials and HSC when you've forgotten all of your statistics and content for topics 1 and 2 (and some of 3). One way to do this is to find a question on the content you learnt that week (and make one a week), or just do them as you get set questions (which could be 3 one week and 0 the next

).
Anyway, kinda rambled a little long haha, but don't worry too much about band 6, just do your best and I'm sure you'll do very well. Don't hesitate to ask any questions you might have on the forum - we're all here to help! Hope this helped out a little! All the best for the HSC year
EDIT: And stuff above. As is typical in the forum someone beats you to post and then you've written all this stuff and you don't want it to go to waste so you just post. Apologies if there's any double up hahahahaha 