How do I enable offline speech recognition?

In order for offline speech recognition to work, you will need to be running a Jelly Bean or higher device (e.g. Android 4.1+).

If you are using a Jelly Bean or higher device, make sure to download the data required for offline speech recognition. 

Below is a screen shot showing the setting in your devices Settings > Voice input and output > Recognition options:

Make sure to install data for each language you use on your device.