Then build from there. Don't get involved in politics. Take office gossip with a grain of salt listen carefully and keep you eyes open. But keep your opinions to yourself. Figure out the corporate culture.
Every company has unwritten rules.
For example, if it's standard to work a 50-hour week, don't expect to go home at 5 p.m. every day. Be prepared to learn on your own. Most companies expect you to produce immediately. Ask coworkers for help, but don't ask too many questions of a single person. Give a token of thanks to those who do help out.