To see these options click the File tab , click Options, and then click Review.
The Review options let you set default settings that determine how the topics and notes content you add during a review will be indicated.
You can assign any or all of the following items to topics or notes that you add during a review:
Assign colors automatically - automatically selects a new fill and font color for each reviewer
Assign Custom colors - lets you select your own fill and font colors
Prefix - specify a prefix (i.e. Mike's idea:)
Icon - select an icon
You can change these settings for the current review from the Review Settings dialog.
Learn more: Review a map