There is a relative subtlety to this particular drawing, partly created by the use of black chalk rather than red. The facial expression of the portrait figure is also particularly down played, reminding some of the Mona Lisa by Michelangelo's Renaissance colleague, Leonardo da Vinci.
The boy portrayed in this drawing is perhaps slightly younger than suggested by his attire. The artist may well have chosen the clothing for this model in order to give a slightly different outcome than if he had just worn his everyday clothes. There is no particular element to the portrait that focuses the eye more than any other - it is deliberately done this way.
Michelangelo put this work together with hundreds of small strokes of his chalk and would have been sat fairly closely to his model in order to go into such detail as well as making him as large as two-thirds life size. The young man captured here had elements that would have appealed to the artist in Michelangelo, plump lips and an innocence of youth.
Artist Michelangelo would take in all manner of different models for his portraits, be it full scale drawings or study pieces for larger fresco projects. Each variation in age, gender and attire would present different challenges and opportunities. In this case he was aiming at the beauty of youth, served up in modest but expensive clothing that presented the model as of good stock.
As with most of his more detailed drawings, it is likely that this would have been given away as a gift. Perhaps the model received it himself, as a way of encouraging the young student to practice his own draughtsman skills. Alternatively, perhaps one of his parents took ownership of this as a memento of their friendship with Michelangelo.