Quick Access Toolbar is a toolbar with a set of commands for you to quickly finish your work. To add a command to the "Quick Access Toolbar", if the command is on the drop-down list, please follow the steps below:
Step 1: Click the small triangle at the end of the Quick Access Toolbar;
Step 2: In the drop-down list, click a command that you want to add to the bar, e.g., "Print Review and Print";
Step 3: You will see the the command is added to the bar.
If the command is not on the list, then you need to click "More commands";
In the new window, select the command from the left box, then click Add to the box on the right.
If you want to add or remove a command from Quick Access Toolbar by using the options commands, please check here for details.