Stop into the new boss's office to introduce yourself, and set up a time to meet one-on-one. Approach the new manager with a positive attitude even if you aren't excited about the change.
The way you welcome your new boss helps shape her opinion of you. If you avoid her, have a negative attitude or seem standoffish, this may send up red flags for her. You may unknowingly create friction between you and your new boss before you really start working together.
Stopping in to say hi makes your new boss feel welcome to the company. Even if the company held an introductory meeting, it's still a good idea to make a personal connection. You also open up lines of communication that are essential for a positive working relationship.
If you didn't schedule the appointment, keep this introduction brief, but ask for more time at a later date. This gives you a chance to feel out your new boss's personality and expectations for the working relationship. Don't assume everything will stay the same. Your new boss will likely have different ways of handling work tasks, communication and other aspects of the job.
The meeting is a chance to introduce yourself and share your talents or duties within the company with the new manager. You can share information about your projects to help her get up to speed on the department happenings.