...before mark this as duplicated: I already tried to perform what is suggested by this and other sites, but without success:
create a usb live with startup disk creator / unetbootin
make a ext2/ext4 partition on the same device with label casper-rw
some suggest to remove the casper-rw file from the usb drive fat32 partition, too.
...the live version will automatically use the casper-rw partition and you will see with df -h that you have 20 gb (for instance) of free space on /
I want to create a usb live device with ubuntu 14.04, then I will perform the (many) customization I need (packages installation, repository changing, many other software installations) and then using it to install on several PCs in my office. The problem is that I need more than 4gb of data to do this. I actually have ubuntu 12.04, so I did the steps suggested above with 12.04 version of startup disk creator (or with the last unetbootin version) but what I obtain is a partition called casper-rw which is mounted at boot as /media/casper-rw (or something similar), and not as /. All the suggestion I've found in internet by now are older than 14.04. Somebody has suggestions?