At least college board makes their old FRQ questions available so you can practice with them. Sit down and do the question in the allotted time with conditions as close to the real exam as possible. Then look at the Scoring Guidelines and grade your self and take note of where you would be marked down.
All The FRQs
Here’s some links to every single FRQ and Scoring Guideline for that FRQ. You can look in FRQs/Solutions folder for sample solutions provided by College Board. Sorry I can’t provide a nicer format than a shit-ton of pdfs.