Google Tag Manager Fundamentals

Complete - This is great course, if you haven't taken the time to better understand using the tool, now is a great time. I would suggest following the steps with your own accounts, just to better understand the implementation steps. You can go in and delete the setup after words but it will give you some hands on training, which I found helpful. If you find yourself stumped go to the community or course forum to get quick answers. 

Tips:
Open Course, AdWords, Analytics and Tag Manager
When reviewing each video lesson right click the "View Transcript" and open each in their own new tab for reference. 

Specifics:
Tag Manager and your website, Other Tags, Implementation, Metrics & Dimensions in GA, Containers, Container snippets, Tag Manager Account Basics, Triggers, Built in variables, Code location, Naming conventions, Property ID variables, Data Layers, Custom Dimensions, Push Method, Dynamic Values, Page view Tags, Custom Metrics, Event Triggers, URL Variables, Conversion tracking, Dynamic Remarketing, Browser Cookies, Help Center

Links: 
Tag Manager Course: www.analyticsacademy.withgoogle.com
Tag Manager Account: www.tagmanager.google.com
AdWords: www.adwords.google.com
Analytics: www.google.com/analytics

Good Luck!