On Windows system, the shortcut of Ctrl + G in Yahoo!Messenger is used to make a Buzz to your chatting friends.
However, Mac system does not provide you a Buzz button or any shortcut to make a Buzz in Yahoo!Messenger, then it is no way for you to buzz your friend.
This article will help you to create a helpful shortcut to make Buzz when using Yahoo on Mac OS.
Firstly, you need to enter into System Preferences:
Then look at the Keyboard part, choose Keyboard Shortcut tab.
Choose the item Application Shortcut at the bottom.
You press + button to add the shortcuts for application.
In Application, look up the installed Yahoo Messenger application.
In Menu Title, type: Send Buzz
In Keyboard Shortcut box, put the shortcut you want to use to make Buzz (e.g.: Cmd+G) similar to Ctrl+G on Windows
Then press Add.
Now you can try Command + G when chatting to see how it works to buzz your friend ^^!