Powerpoint pres. with sound on a flash drive?

I did a powerpoint pres. on my home computer with .wav files from the internet. I need to take the presentation to school tomorrow with the sound playing in the presentation. When I copied the presentation to my flash drive, there is no sound. Help! How can I get the sound to go with the presentation on my flash drive. I googled this all day, and don't understand how to "embed" the sound to my presentation. Can anyone help with step by step directions? How do you copy the sound files into the folder with the presentation?