Add Class trigger event in Google Tag Manager

1. Workspace
2. Variables
3. Built-In Variables -> Configure
4. Add, Click Classes, Click Element, Click ID

Then go to Triggers

1. New
2. Name the Trigger
3. Click the ‘Pen’
4. Add ‘All Elements’ (under Click section)
5. Change to ‘Some Clicks’
6. Add: Click Classes, matches RegEx, classname (if multiple classes, use: classname1|classname2|classname3)
7. Add: Click Classes, equals, button

Then go to Tags and give the Trigger to you Tag.

Remember to Submit your changes