I work similar to how DaveRo and others said with starting at the end. But I tend to change it up more, sometimes I start in the middle, sometimes the end, and sometimes at the top. I've found if I always start in the same spot, that's the only part that I end up remembering well.

But my favorite thing to do is to sing the song in a variety of accents/silly voices. It works the same as writing in longhand, your brain has to slow down to think about the words/phrases more (and also it's just fun)