1? You first add a playlist to itune and call out your singer's name. then what
2? You went back? The interface of all music? Click the third button in the upper right corner? The one at 6 o'clock? At this point? The performer found all your singer's songs? (pictured)?
3? Double-click the picture above the singer's name to find all the songs. Press crtl+A? Colour all the songs blue? Click the right mouse button to find "Add to Playlist"? Just select the list you just mentioned.
4? Finally, just synchronize the music.