Debian 7.9 installed into Lenovo X1 Carbon

I installed Debian wheezy 7.4 into my laptop and wrote the article, Lenovo X1 Carbon へ wheezy 7.4 をインストール - Shammerism. At that time, wifi firmware is located at the USB memory root directory. But, this location seems to be changed according to http://d-i.alioth.debian.org/manual/en.i386/ch06s04.html.

At wheezy 7.4, iwlwifi files whose extension is ucode must be located in the root directory of a removable USB memory. But, 7.9 requires that ucode files must be saved at $RemovableUSBMemory/lib/firmware.

I had no idea about this change, so I couldn't install until I found this information. I will summarize the procedure how to install and set up my debian wheezy 7.9 on my laptop, Lenovo X1 Carbon. I try writing this article within a couple of day, though it seems to be a little bit hard for me.