If you want to run Favorite Commands using the Keyboard, use the Alt+[number] keys.
In order to add Favorite Commands to the Quick Access toolbar, you can access
- Home => Preferences => Toolbars => Toolbar: Quick Access
- or Right Click on Quick Access Toolbar => Customize
then you can select the ones that you have previously defined (as described in the other answers) in the category
[+] Home => [+] Favorites => [+] Favorite Commands.
I am using R2018a.