How can I prepare a file with contacts to import?

How can I prepare a file with contacts to import?
SquizMAIL support import from .csv (comma separated values).
Import under contacts management.

e-mail marketing - Show my contact lists

Double click on the previously created mailing list or create a new one.
e-mail marketing - New contact lists

Select import.
e-mail marketing - Contact Import

In the first line of every column you can write column names so you don’t have to map them later.
Each information (first name, last name, email …) must be in a separate column.
If you have written column names in the first row, then you have to select the following option.
e-mail marketing - Contact Import