To enable the Aly&AJmoji Keyboard, go to Settings then Personal and finally Language and Input.
Under Keyboards and Input Methods, you’ll see the Aly&AJmoji keyboard installed on your device. The exact name of the menus varies by manufacturer: On the latest HTC phones, for example, you head to Settings, then Language & Keyboard.
To enable a keyboard, simply check its box and Voila! – you can now use that keyboard whenever you’re typing in a text box.
To set the default keyboard, tap Default and choose your desired input method.