Once the app is installed, sign in to your library via the app and follow the steps below:
Step 1
Choose the audio you want to download and click on download your audio.
Step 2
On the next screen, click Download Your Audio.
Step 3
Under Downloads, click on the name of the audio which will start the download.
Step 4
Your audio will then be saved to your Files folder on your device. Find the audio there and click on it to play.
You can now listen offline (also works in airplane mode).