RECOMMENDED EXPERIMENT SET UP IS GIVEN ON THIS PAGE: http://www.buildcircuit.com/mp3-mode-circuit-wtv020sd-16p-tutorial/
Power supply: DO NOT use 5V power supply for the project. 5V will burn both your MicroSD card and the music module. Use 3.3V power supply only. You may use a 3.3V regulator chip or get power from Arduino.
Other points:
a. Micro SD card: Use a 2GB SANDISK MicroSD card. I have tested with 1GB card, but it didn’t work. Some customers have said that the module also worked with Kingston 512MB MicroSD card. You can buy a SANDISK 2GB micro SD card from www.buildcircuit.org.
b. Music file format: *.AD4.
c. File names: 0000.ad4, 0001.ad4, 0002.ad4 and so on. Download Sample Files
d. After you make the first circuit on a breadboard, press the NEXT or PREV switches for at least 5 seconds. If all the connections are correct, your music will play.
e. Try this experiment first: http://www.buildcircuit.com/mp3-mode-circuit-wtv020sd-16p-tutorial/
f. Read this article carefully: http://www.buildcircuit.com/how-to-use-wtv020sd-music-module-with-arduino/