Its quite funny and disgusting, I can understand your situation. I failed at first attempt due to nervous and I was not inform by my instructor to review such traffic signs and never give me a copy of those signs. I just did on the day itself so I failed.

You just have to review and memorize all signs by heart and mind. you can practice it also while on road by looking at every signs you see and identify it.

Lastly, Don''t be nervous make your mind at peace and concentrate.