She left London for China as a second-class passenger on the P&O vessel Kaisar-i-Hind I in January, 1888, age 22. The Hundred missionaries had all sailed to China the previous year. Among the 25 passengers (16 men, 5 ladies [sic]) aboard the steam ship with her were Miss Mary Reed (daughter of Mrs Henry Reed and sister of Mrs Harry Guinness), Mr and Mrs Hunt (travelling to Hanchung) and the Pigott family of The Sheo Yang Mission (who were eventually killed during the Boxer Rebellion).
As recorded in In the Far East (1889), the Kaisar-i-Hind took a route passing Gibraltar (10:30pm, 31 January 1888), calling at Naples and then passing the Straits of Messina, stopping for a day at Aden and then onward to Colombo, Ceylon.
At Colombo the missionary party boarded the P&O vessel S.S. Deccan, bound for Shanghai. A stop in Penang, Malaysia, allowed Geraldine a first contact with many Chinese who came on board. Then a stop at Singapore followed. Her first time on Chinese soil was later at a stop at Hong Kong where she was received by Dr and Mrs Chalmers of the London Missionary Society, who introduced them also to Mr and Mrs Bender of the Basel Mission. Shanghai was reached next. But Shanghai was not their final destination. Staying only long enough to exchange their European clothes for the national Chinese costume, the missionaries started on again, leaving this first station of the China Inland Mission behind them and travelling on the boat Fuh-ho ("Happy Harmony") in the substantially cheaper Chinese accommodations up the Yang-tsi River to Chinkiang. Lastly on to a barge some 6 hours to Yang-chau, finally arriving at Yang-chau on 23 March 1888.
She wrote to her sister after a short time in China:
Oh! if English Christians only knew the need and the longing willingness of these dear souls to hear the glad tidings, and the joy, the unspeakable joy of a missionary's life, they would surely cry from the depths of yearning hearts, "Lord, here am I, send me, send me."
After training in China, Geraldine was eventually stationed in Honan Province.