I have bought a USB cable, but spent some time trying to use the Arduino.
Fortunately, I have succeed with it. You should do the following:
1) connect arduino to the cable: GND-GND, VCC-VCC, TXD-RXT, RXD-TXD
2) start Arduino IDE
3) select Board->Arduino Pro or Pro Mini
4) select suitable processor (ATmega 328 (5V, 16MHz)
5) select valid COM port, corresponding to the USB cable
6) prepare your sketch, press Upload button
7) the most important(!), press RESET button on the arduino when Arduino IDE shows "uploading in the status bar"
8) it works!