Third step would be adding a microphone.
- Click on Source in the left menu
- Now switch to Audio Sources tab
- Press Click to add
The first available audio source will automatically be selected.
- Change Audio Source in the pull down menu in case you want another input source
- In most cases select Master Volume at the Audio Input pull down menu
- Increase the default Audio input level
- Commit your settings with Insert
NOTE: You can add up to 4 audio inputs. However, during a recording you can not switch!