Download the codes here Arduino simple shield potentiometer code: Arduino shield rc car: Arduino nano module L298P code: ...

Click Sketch > Verify / Compile to make sure the code is properly in there. Save the file and then attach the Arduino to your computer with the USB cable. Click File > Upload.

The complete list of fixes and credits is available here. For more information on the latest Arduino IDE 1.6.6 and to download the latest version jump over to the Arduino blog via the link below.