All Mac OS X users know that Apple implemented since OS X 10.8.2 the ability to dictate to the Mac the text we want to write. This option is also available on iOS but in the case of the Mac it can be configured to easily activate it by pressing a hotkey.
The dictation function, at least in the iMac Late 2012 we have it available if we press the 'fn' key of the keyboard, but we can always modify this predefined key and choose the one we want or simply use the other options of the system itself to define access to this function.
As always, to change this predefined key or in the case of not having the quick function assigned to any of the keys, we will access its configuration from the menu and then pressing on System preferences.
Once we have the System Preferences window we will have to access the option 'Dictation and speaking' and in it we will see the 'Dictation' tab, we see that it is activated and we continue with the edition.
At the bottom we will see the option 'Quick function' if we press, the drop-down will open with 4 options available by default and the Custom option
We select the option we want to activate the dictation option and we already have the key assigned to use voice dictation on our Mac, if we choose the 'Customize' option we have to bear in mind that the selected key should not interfere with our tasks, it is say, choose a key that we don't use often if we don't want it to be activated accidentally.
I personally have the quick activation option selected with the right 'cmd' key twice, but this is up to everyone.
More information - Use a keyboard and mouse for two Macs
Hello. As it happens to another person, I activate dictation, the microphone comes out, I accept, then I speak and do not write anything.