How do I stop my iMessages appearing on my MacBook Air? I updated my MacBook Air to El Capitain (OS X 10.11)
I would rather not have my messages appearing on my Mac when others are using it.
I have tried System Preferences but I cannot find the Accounts tab in my settings.  Any help would be greatly appreciated!
The best practice would be to have other users set up with their own logins on your Mac or to use the Guest account.  They would never see your messages in that case.

But, if you really wish to disable iMessages from appearing on your Mac:


Go to Messages
Open the Preferences Messages > Preferences or ⌘+,
Go to the Accounts tab
In the iMessage account uncheck "Enable this account"