How can I transfer songs onto my iPod Touch playlist?

So I just recently got the new iPod touch (5th gen), and I used to have an old iPod. The songs from my old iPod are still on this iTunes playlist, but i want to replace them with my new songs on my new iPod. The thing is, whenever I go click 'iPod' and go to the 'On This iPod' tab, it shows all of my songs on my new iPod, but it will not let me drag the songs from my folders to the playlist. How else can I transfer songs from my folders to my new playlist?