?udio in signal prepare and serial.

I want to receive a mono audio signal from a source (dtmf tone generator with 3,5mm audio jack output) and send the value to the com port.
Little looking online I have understood that the Arduino can receive signals 0 to +5 volts.
And the audio signal from the device comes with negative and positive values.

What is the easiest way to prepare for the reception signal to an analog port Arduino?
Maybe somewhere there is a very detailed diagram Wiring for Dummies?

https://www.google.com/search?q=arduino+audio+signal

this would be the best answer