How can I silence the ringtone of an incoming call?

There’re several ways to silence the ringer before answering a call.
Method 1: Press the Volume Down/Up or Power button on the side of your device.
Method 2:Go to “Phone” app->touch menu icon at the top right corner on the screen->touch “Settings” -> “Flip to silence” and activate “Flip to silence”. You can then mute incoming calls by turning the phone over when a call is being received.
Or Go to home screen->”Settings”->”Button & gesture”->”Gesture”->”Flip to mute”->active “Mute incoming call”.
Note: To disable the “flip the device to mute” function, disable both “Flip to silence” and “Flip to mute” which mentioned above.
Method 3: Go to menu -> “Settings” -> “Sound & vibration”-> activate “Silent mode”.
Method 4: Drag the Status Bar down with your finger and then touch the “Sound” icon to change to “Vibrate” or “Mute”.
Note: Press the “power” key and “volume up” key at the same time to switch to vibration mode quickly.