Unable to choose any Macro Instructions when creating a New Macro in Salesforce

1. Enable Case Feed.

2. Create Global Action or Object Specific Action.

To know about Actions in Salesforce, check the below link

http://www.infallibletechie.com/2013/07/actions-in-salesforce.html

3. Edit the case layout and add the Quick Action.

Note:
Macros will only work with the new Case Feed Layout. Legacy Case Feeds is not supported.

Cheers!!!