You would first download iTunes 11.1.3 or the latest at that time. Keep in mind that just because it is old does not mean it doesn't work at all. An example would be a classic iPod Shuffle the skinny one. I heard that iTunes 11.1.3 does not support that iPod and that you would have to stay with iTunes 10.9. And then if you have iTunes 11.1.3 you would click on the iPod bar on the top right hand side by the iTunes Store icon and then you would click on the bars to tell your iTunes what to sync to your iPod. Also keep in mind if you remove it from iTunes before ejecting it, you will not get what you have synced on it if someone removes it or knocks it loose from the USB port(s). Also to update software click on the check for software update button on the iTunes 11.1.3 and it should be there on the about my iPod or something like that. Also it will name your iPod to your name like for example Jon Doe. And you NEVER EVER EVER want to sync it with anything other then iTunes.
iTunes Helper 2013