The RSS page on CanLII provides links to subscribe to specific federal or provincial Acts and Regulations so that you are made aware of any legislative changes.
Simply browse to the Act or Reg you are interested in and click on the blue RSS icon to set up the feed.
Alternatively, you can subscribe to all Acts or Regulations to be alerted to changes to all Canadian legislation.
A customizable RSS feed is available on the Bills page. Search for your Bill and in the results click the RSS icon to access the feed.