Lazy Line Painter Jane Lyrics

Lyric discussion by Reiver 

Cover art for Lazy Line Painter Jane lyrics by Belle & Sebastian

I have a couple of points: 1) Why am I the first person to comment on this, when it's one of the best songs ever recorded. 2) I think I get the meaning of almost every word in the song, about a mixed up girl with a bad reputation. But why the hell is she 'painting lines'?