To install the application run the file FreeConvertMP3ToWAVSetup.exe.
Press the "Next" button in the first screen.
Afterwards, select the directory where the application will be installed, or simply accept the default one and press the "Next" button.
After the application is installed you can start it by clicking the Free Convert MP3 To WAV shortcut icon on the desktop or by selecting the Free Convert MP3 To WAV shortcut from the Windows start menu.