Generating the CSV
To export the .csv file from Outlook 2013, under the File tab click on Open & Export:
From there launch the Import/Export wizard:
Choose Export to a file and then Comma Separated Values (CSV):
You will be presented with a list of Outlook folders. Selected a contact folder and then click Next to save to a .csv file:
This should produce a .csv file similar to the attached.
See the CSV Import File Format solution for details on supported columns when you are ready to import.