Experience in other programming languages and data modelling probably help. But there are lot of QV specific topics, so there is nothing that will pay off more than experience in QV.
They are saying that you should have some months experience, and I think that should be a reasonable amount of time.
If you are following the discussions here in the forum, as soon as you can answer most of the questions in a short time and on your own, this should give you an idea when you are ready.
This is also a great way to learn, try to understand the presented solutions in depth and maybe then try to develop a different approach.
Note sure if this helps, but just keep up going,