A test you can do is a Chart of the Alphabet. This link shows the pre-anniversary edition (if you are doing that edition, you can skip over that part). Can you complete one? Even if you did one, can you make another one? I don't think you need to do it perfectly, but maybe if you think you're finished with Advanced Shorthand, then do it perfectly.
"Gregg Shorthand had achieved the most extraordinary success ever attained by any system in the history of shorthand." John Robert Gregg, 1922