How you behave when you are a newcomer in the company?

Listen and learn, instead of talking in one. Eat your energy observing and asking intelligent questions instead of trying to convince others how much you know and how important.
Be kind, equally with everyone.
Do not rush to make judgments about who you think is smart, important, nice. Along the way, you can change his mind about the many colleagues in the office, so it's not wise to make statements about someone before you know better and see the acting.
 Invite your colleagues at the table and try to know them informally.
Do not ask personal questions about others in the office. If you try to find gossip, you will soon choose a reputation that you do not want, you will be considered a person can not be trusted.
Wear tight administrative staff.