Conversation so far:
How did Henry Irving's career begin?
On 29 September 1856 Henry Irving made his first appearance at a Sunderland theatre as Gaston, Duke of Orleans, in Bulwer Lytton's play, Richelieu.
Was Henry Irving successful as Gaston, Duke of Orleans?
The inexperienced Henry Irving got stage fright and was hissed off the stage in his first acting role.
What did Henry Irving do after getting hissed off the stage in his first acting role?
For 10 years, Henry Irving went through an arduous training in various stock companies in Scotland and the north of England, taking more than 500 parts.
What was the result of 10 years of training at theatre companies for Henry Irving?
Henry Irving gained recognition by degrees, and in 1866 Ruth Herbert engaged him as her leading man and sometime stage director at the St. James's Theatre, London.

Question: How did he do this?
Self-contained rewrite: How did Henry Irving do as stage director at the St. James's Theatre?