Ms. Sim graduated cum laude from the University of Southern California in 2004, receiving a Bachelor of Arts degree in Journalism, with departmental honors. Ms. Sim also had minors in Communication Law & Media Policy and Natural Science. In 2007, Ms. Sim received her J.D. from UCLA School of Law in 2007. During law school, Ms. Sim externed for the Honorable Maria Rivera, Justice of the California Court of Appeal, First Appellate District, and was a managing editor of the UCLA Entertainment Law Review.

Upon graduating from UCLA School of Law, Ms. Sim served as judicial law clerk to the Honorable Whitney Rimel, United States Bankruptcy Court, Eastern District of California. Ms. Sim is a member of the State Bar of California and is admitted to practice in the United States District Court, Central District of California.