How did Don Jaime become a fencing master in the novel, The Fencing Master?

After he escaped from the army, Don Jaime settled in Paris where he was introduced to the fencing master Lucien de Montespor. Initially, he only acted as a type of runner, delivering towels and drinks to the students, however as he learned the trade Montespor entrusted Don Jaime with his beginner students. Don Jaime continued to develop his technique and when Montespor fell ill, he decided his time had come and he enrolled and graduated from the Paris Academy of Arms as a fencing master.