How do i do a bulk import of contacts?

Section: 
Campaign Creation

You can import bulk contacts from webmail (yahoo, gmail, aol, msn) (or) you can import the contacts from files (in case you wish to export from a desktop mail client, you can export in csv (or) excel format) and convert to the format needed for upload in to the application.

cannot be empty.
is invalid.
Please select
Could not save. Please fix the indicated error(s) and save again.