Kammala jumla mai zuwa: A ranar 18 ga Disamba 1855 Stephenson ya shiga Royal Navy, ya zama Naval Cadet a HMS "St Jean d'Acre", wanda kawunsa Henry Keppel ya umurta, kuma ya yi aiki a cikin Bahar Maliya a lokacin Yakin Crimea. Daga watan Satumbar 1856 zuwa Afrilu 1857 Stephenson ya yi aiki a karkashin Keppel a matsayin ɗan takara a cikin HMS "Raleigh", yana aiki a Gabashin Indiya da China a lokacin
Yaƙin Anglo-Chinese na biyu, har sai jirginsa ya rushe kusa da Macau lokacin da ya buga dutsen da ba a san shi ba. Dukkan ma'aikatan jirgin sun tsira. A watan Yunin 1857 ya yi aiki a matsayin Midshipman a cikin HMS "Pearl", yana aiki tare da "Pearl's Naval Brigade" a lokacin Tawayen Indiya na 1857, wanda aka ambaci shi a cikin Wasiku sau uku. A watan Yunin 1861 an ba shi mukamin Laftanar a cikin HMS "Emerald", yana aiki a cikin Channel Squadron.