Accept invitations - In a new job, accept your first few invitations to lunch or happy hour. If you decline them, for whatever reason, they will stop, and you may find yourself an inadvertent outsider.
Don't look too busy - Some smart and dedicated employees fail to get promoted, because they have taken on too much, worked too hard, and appeared too frazzled. If you appear stressed, people will think you aren't prepared to take on more, and you'll miss opportunities for new and innovative projects.
Do more - As you move up, your future success depends on doing unassigned work and responsibilities. Anyone who made it past the hiring process can do the assigned job at the company, but it takes a lot more to deliver value to the company that wasn't assigned or even thought of.
Help others - Even if there is no direct benefit to yourself, just do it. It takes so little energy to answer questions, provide referrals, and open doors for people who need your help, even if doing so offers you nothing immediate in return. Your efforts will be rewarded in the future in wholly unexpected ways.
Know your weaknesses - The weaknesses that you're unaware of will hurt you the most. This is your blind spot. You must determine your hidden weaknesses and work to overcome them, and you're going to need the help from others to do this.
Copy from others - When you want to learn some skill, look around for someone who is already good at it. Then just watch what they do, and copy it. Find what works for you, and modify it to your own abilities and style.
Ask your boss - Find out what his biggest problem is, and make it go away.
Look sideways - Don't just focus on those above you - look laterally as well, because people with diverse experiences usually progress faster than people with more experience.
Entitlement is a career killer - Focus on staying grateful and working hard rather than feeling that things are owed to you.
Make it easier for them - Try to make the next person's job down the line easier. If you are working on a project that goes through different hands, see what kinds of things you can do on your end that will make the process flow easier for the next person who performs the next step.