So I have not actually practiced any online tests prior to the online test. The test link comes with some practice questions and I just did that.
However I would like to add that I did a variety of data crunching, etc in my projects generally and that helped me.
If you are in the same path, you will be fine with what you have learnt from your experience.
If i remember correctly, it is focused on simple numerical calculations and finding relevant data in the question quickly (from graphs, tables, etc)
Hope that helps.