In this post I will create an empty container database using dbca. The dbca tool has been around since Oracle 9i (before it was dbassist, if you remember ...). You will find the tool in $ORACLE_HOME/bin, it's graphic based, so you should set the DISPLAY if you work on Linux. Ok, startup dbca. Follow the screenshots.
Select the Advanced Mode, Next.
Now just wait until finished. This strongly depends on your speed of hardware.