If you have a smartphone on the Vodacom network then you have 2 options to send 20 free SMS (to other Vodacom numbers) per day.
1. The easiest option is to just install the My Vodacom App (available in the App Store / Google Play / BlackBerry World) and login using your Vodacom website details to send Free SMS.
2. You can also access the desktop version of the Vodacom website from a smartphone. Just head over to vodacom.co.za on your phone (this will load the mobile version), scroll right down to the bottom of the page and select the 'Switch to the full site' option or click the direct link here: http://www.vodacom.co.za/personal/RedirectFullSite - This link will load the desktop version of the Vodacom website on your phone and you can login to send free SMS.