I remember when I was having a hard time with these symbols as well. I think the main reason is that there is so much going on in one symbol. They way that it helped me was to understand that it was really two symbols put together. The traveling arrow and the rotation arrow. I have found that the reason many people have a hard time understanding the combination is not because of the traveling arrow but the rotation. I have found that it isn't an easy one to teach with just words. I have to show someone how rotations work. ;-)
Here are some writings of rotation and traveling arrows separated, and then together.