US 20 year old in Korea in June/July needs visa for University Games in Chengdu in later July

Hello,
My daughter is a member of the USA archery team delegation going to the World University Games in China this year. She will be training in S. Korea from June 14th until July 21st. There is not enough time to get a visa in the United States as she is leaving shortly for S. Korea (June 14th). She already has an invitation letter from China. What are her next steps in terms of filling out the application for visa and then making an appointment at the Visa Center in Seoul,Korea?