When greeting another man, always use proper handshake form. The crest between the thumb and index fingers on both men must meet firmly but briefly. Two shakes are appropriate for business settings.
Outside of the business world, a nod is usually sufficient:
- When greeting a friend or buddy, use an upward nod of the head to signify familiarity and casualness.
- When greeting any other fellow man, use a downward nod to signify the unspoken man code, and the refusal of any form of challenge.