There were no forms for candidates to fill in, little attention was paid to qualifications and he did not draw up shortlists.
A typical example was Leonard Hussey, a young man with impressive qualifications in fields like meteorology and anthropology. Shackleton looked him up and down, walked around the room and announced: “Yes, I like you. I’ll take you.” Shackleton elaborated a little by telling Hussey: “I thought you looked funny.”
as I recall there were a LOT of candidates, i think “low wages” , “extreme danger” and hardship were among the little advertising. Fitness, ambition and a good reason were wanted and i believe the add mentioned something about “fame” , aka a good reference to any who ‘made it back’!
Shackleton was famously poor at planning his expeditions. But his recruiting methods were simple and effective. Advertising low wages and extreme danger sacred off a lot of posers and time-wasters in the application process. He had an outstanding third sense about the men he hired. I think this derived from his merchant marine background. He could sense the men with the toughest mindsets.