It only occurred to me recently that students don't always know how to learn quotes. I had presumed that writing a quote out a number of times is the best way for every student to revise. However, if we are to believe that students have different learning styles, we should also acknowledge that they should revise in different ways.
Here are some suggestions:
Visual learner - (you tend to close your eyes, or look up to 'visualise' something in order to remember it). Writing a quote out repeatedly will help. It would also be helpful to put quotes down for different characters on different coloured cards.
Auditory learner - (you verbally process things, by reading out loud). Saying quotes out loud will help you to remember them. It might not be as helpful to just write them out.
Physical learner - (you are not keen to sit still!) Then pacing up and down whilst you repeat the quotes might well help.
It's a matter of trying a few different ways out. Students are often under the misconception that just reading over information a few times will surfice. It rarely does when tested!