Man greeting Man - Men shake hands when greeting one another and maintain direct eye contact.  Many give each other a kiss on the cheek accompanied by a light hug/grasp.  A warm handshake is the way to go for a first meeting.  Hugs are common between good friends and family.

Woman greeting Woman - A kiss on the cheek is common if two women know each other.  A light handshake is the norm if they are meeting for the first time, especially with foreigners.  Sometimes a simple nod of acknowledgment will do.

Man greeting Woman - At a first meeting it is best to allow the woman to offer her hand before trying to shake it.  Light handshakes are the way to go.

Note: Always use and offer your right hand to shake if possible.   It is taboo for religiously observant men to touch women and vice-versa.