@ AC Learn songs starting at the end and gradually add bits till you get to the front. Starting at the end counters the natural tendency to shortchange the latter parts of songs in the usual learning/rehearsal process.

I have been in choirs where the director started teaching the song from end or the middle. I sort of built the mnemonic with pictures that tell the story for the line for the last song I did and it worked.

Studies have been done on how actors remember lines and it was discovered that staging plays a huge role in prompting the memory. So spot on with the physical movement and facial expressions thing.

But I do like the copying out the lines 2 or 3 times idea from Best-bet. You start actually seeing the next line in your head.