Include parameters by adding them to the URL in your offer, and link in the SMS.
All parameters appear in Campaign -> Offers -> URL Shortcodes, and include:
Conversion tracking: Dynamic
User attributes: Phone, Name, Email, Geo
Campaign attributes: Ad text ID, List ID
Add parameters in query string in name-value pairs, for example: http://www.site.com/?d={{{dynamic}}}&email={{{email}}}
Save your offer, add it to your ad text, and you're good to go!
*geo is 2 charters string