Hi, Alessandro. I'm not Chinese, but I learn Chinese too. I think it doesn't matter what paper you use. But you should use squared notebook like this. There are 4 squares for one character. You can make it in Microsoft Excel. http://4.bp.blogspot.com/-aMmVn-3d_Pg/UZMCrayQL1I/AAAAAAAAAPo/W8rwFh3RbhI/s1600/write-chinese-calligraphy3.gif I'm used to do it in my squared notebook: http://cs619124.vk.me/v619124851/25d9/LAKoAHV4fyY.jpg

at first use "copybook" which is called "字帖".then use the papper with square blank called"田字格“

I notice most of people here are talking about practicing calligraphy, I mean like using brush and ink. I thinks for us as beginners calligraphy is a very high level skill. I think for you a basic practice is just ok, you can get a page with big squares, then try to suit the letters just in the square space, and repeat sooo much times. That's basically the way to practice.

use just common lined paper... usual lines

what are you studying Chinese calligraphy fonts？