Need help with Vista 32 bit Home Premium

Hi All need help with sound for 32 bit home premium. It is a new comp /
OS that I am unfamiliar with, I cannot get no sound so the new
speakers are sitting on the floor. When I tried to run a sound test
nothing came thu although the taskbar shows realtek audio speaker
volume at 66. When I plugged in the speakers the desktop pop up
showed..(rear speaker, front speaker and surround etc.) how to you set
thos up so the speakers can work? thanks for your help..