Great so now you know what a Google Annotation is and what you should be taking note off... so how do you add a Google Annotation?

Luckily this really is easy to do!

Choose the option to look at your traffic in "Audience Overview" and at the bottom center of your graph is a little down arrow.

All your saved annotations will then show and you click on "Create new annotation" to make a new annotation.

You can then edit the date and add your notes as needed as shown in the screenshot below:

You can make your annotation private or shared. Shared is for if there is anyone else that has access to your analytics and you would like that person to have access to your annotations too. Otherwise you can make it private.