title: Implement custom events in Google Tag Manager when I don't have access to the Tag Manager site
body: <p>I'm building a site for a client who uses Google Tag Manager,  they have sent me the javascript snippet to include on every page.<br>
  Now they are asking me to create custom events for certain user interactions. </p>
  
  <p>My understanding is that I need to define these events within the Tag Manager Site  first. Is that correct?
  But, How can I do this if I don't have access to the client's Tag Manager account? </p>
  
  <p>Using Google Analytics (GA) I could just call ga() function in JS,  with the event name and parameters as arguments. I didn't need access to the GA management site itself.     </p>