You can read the Cynegeticus online in English at the Perseus Project.
Xenophon opens the treatise by noting that hunting is a gift of the gods, having its divine patrons (Apollo and Artemis), who gave the art to Cheiron the centaur, who then taught the great heroes of Greece: "Through the heed they paid to hounds and hunting and the rest of their scholarship they excelled greatly and were admired for their virtue" (1.5). Xenophon thus thinks of hunting as a form of education, one "by which men become good in war and in all things out of which must come excellence in thought and word and deed" (1.18).
Indeed, we find in Chapter 2 that he takes hunting to be a sort of foundational education, the kind of thing one should start a boy out with before branching into other things. He then gives practical advice on the kind of outfit and equipment one should have (Chapter 2), the kind of dogs one should look for (Chapters 3 and 4), how to go about hunting rabbits (Chapters 5 and 6), how to breed and name dogs (Chapter 7), how to track rabbits (Chapter 8). He then moves on to deer (Chapter 9), boar (Chapter 10), and then big predators like lions and bears (Chapter 11).
Having given practical tips, he looks at the advantages of hunting: "it makes the body healthy, improves the sight and hearing, and keeps men from growing old; and it affords the best training for war" (12.1). It is a kind of training in truth, as well, requiring restraint and fairness, and at least occasional self-denial. This is not a sufficient condition for virtue, but it is necessary; people who are driven to indulge in pleasures cannot achieve virtue.
This principle, and the art of hunting, is inconsistent with the education given by the sophists:
We have never seen anywhere the man whose goodness was due to the sophists of our generation. Neither do their contributions to literature tend to make men good: but they have written many books on frivolous subjects, books that offer the young empty pleasures, but put no virtue into them. To read them in the hope of learning something from them is mere waste of time, and they keep one from useful occupations and teach what is bad. Therefore their grave faults incur my graver censure.
Xenophon says that, unlike the sophists, his intent is to write a good book on a good subject that helps to make men good, advising everyone to avoid the sophists, who are hunters of the rich and young and not, like philosophers, friends to all. True hunters will hunt wild beasts, but sophists and wicked men hunt their friends; true hunters hunt for necessity or the good of others, but sophists and the like hunt for private gain. And Xenophon ends with a comment that shows him to be a true inheritor of the Socratic concept of education:
For all men who have loved hunting have been good: and not men only, but those women also to whom the goddess has given this blessing, Atalanta and Procris and others like them.
Quotations are from Marchant's translation at the Perseus Project.