Imagine if my friend woke up from a 10 year coma, what would you suggest my friend does to improve Google analytics?
Create custom reports. We can find out the activity based on time of day or how your content performs with mobile users. This would help uncover what time of day drives the most traffic and/or sales. What other custom reports should be added?
Use event tracking.This can help my buddy better understand how people are engaging & flowing on the site. What else do you like to uncover with event tracking?
Set up goals.Some people may feel paranoid about goals and letting Google know what actions you value on your site. If anyone is paranoid they can create a fake thank you page with a $1 million dollar goal value and they will quickly discover there is little reason to worry about creating goals in Google Analytics. Setting up goals does help you better understand your conversion funnel which will help you better achieve your site's business mission.
Filters - Let's get rid of the internal traffic and the external analytics spam traffic. It can seem scary to apply filters which lowers the traffic but you don't want to marketing decisions based on fake traffic from spammers. What are your favorite filters?
Integrate with other Google Products. Make the most of Google Analytics by integrating it with your Adwords & Webmaster Tools. More information will make it easier to make smarter decisions.
What other advice would you give to my coma friend to improve Google Analytics? What are your most helpful filters, custom reports, etc?