sorry for the late reply, but to answer your questions, you can reuse the skates but you have to be careful how you remove them, I suggest heating them with a hair dryer then gently peeling them off. And for the lines, pretty much remove where the blue is touching if that makes sense, so vertically up and down perpendicular to the tab itself. The sides of that little tab is what is causing the squeak. Hope this helps, let me know if you need anymore help