Most DMVs accept walk-ins. There are also DMV offices that allow you to schedule your Driving Exam. You should do whatever option feels most comfortable to you. You can visit this website to find out more information about whether you should schedule your DMV exam and how you would go about doing so if applicable: http://www.ncdot.gov/dmv/contact/.
For your NC Driving Exam, you should demonstrate to the examiner that you know how to drive safely and efficiently. You should feel comfortable, for example, passing through intersections, coming to a complete stop at stop signs and traffic signals, backing up safely and making three-point turns successfully.
You should practice regularly and consistently. You should always be accompanied by a licensed driver who is 21 years or older when you are driving. You should begin practicing and driving on streets that aren't busy and then slowly progress to driving on busier streets, where you will develop skills that help you drive safely alongside other vehicles.
You should make sure a licensed driver who is 21 years old or older accompanies you, and you should bring your NC Learner's Permit and proof of your car insurance with you. If you are under 18 you should provide documentation that demonstrates the 60 hours of behind the wheel training you have completed.