Usually remastering ubuntu use remastersys, but know remastersys discontinue. After googling I found softaware Re-Linux. Re-Linux is remastersys fork, download at http://nchc.dl.sourceforge.net/project/re-linux/relinux_0.2b1.tar.gz, How to install:
1. Extrack file relinux 0.2b1.tar.gz
2. Open terminal, enter to directory, type cd foldername
2. Open terminal, enter to directory, type cd foldername
3. Install with command:
sudo cp -R usr etc /
4. Finish. For manual check /usr/share/doc/relinux/README