Sketch the brachial plexus repeatedly.
Understand how the ventral rami connect and re-organize to form the brachial plexus. Map on muscles innervated, ranges of motion, sensory territories, etc.
**Remember to do this for both right and left sides**
After you understand how the brachial plexus is organized, visit YouTube to find videos that teach you to sketch it in less than 30 seconds.
When the exam starts, quickly sketch the brachial plexus. Quickly add notes/mnemonics you need to refer back to. This way you can refer to your sketch as you answer questions. This will cut down on confusion or recall accidents during the stress of the exam.