- install bzr: sudo apt-get install bzr
- copy eOS code branch: bzr branch lp:elementaryos
- cd to the dir: cd elementaryos
- Edit the config to suite your needs: cd etc && nano config
- You can specify the architecture to amd64 or i386, also tweak some things like base or version number (you should leave those as is).
- Add elementary daily ppa: sudo add-apt-repository ppa:elementary-os/daily && sudo apt-get update
- Go back to the main elementaryos folder and execute ./congrego.sh it will tell you about required packages. Install them and run it again.
- When done builds will be in the builds folder.
This project is putting up builds on sourceforge also if you don’t want to do it yourself > https://sourceforge.net/projects/eosbuilds/files/isis-unstable/
I would try it on a VM because this is pre-alpha software. Also you should report bugs to help development at https://bugs.launchpad.net/elementaryos
note: Reposted from the defunct Tux Fiction blog.