Use the built-in call recording feature if your phone and carrier support it
Open the Phone app during a call
Tap the Record button if it appears
Check the Phone app settings for Call Recording
Enable automatic call recording if available
Use speakerphone and another device to record the audio
Use a voice recorder app on a second device placed near the phone
Use a Bluetooth headset with recording support if your device allows it
Check your local laws before recording any call
Inform the other person before recording if required by law