Trade information when it's required, but don't fan the flames of gossip with your opinions. If in doubt, remain silent. Link your personal goals to the strategic goals of the organization. Keep your employer's perspective in mind and do whatever you need to do to advance your cause. Just make sure you don't deliberately defame or injure another individual.
Nobody wins unless everybody wins.
This may sound obvious, but if you behave decently, you'll avoid a lot of the crap. Don't oversell, just be natural. These subtle political tactics will preserve your integrity. Politics can be, and often are, abused in the workplace, but they can also be used to do great good. Even when you're out to get something done, not to do someone in, you have to play politics.