Starting with should obviously be done by creating master and work repository
http://www.oracle.com/webfolder/technetwork/tutorials/obe/fmw/odi/odi_11g/odi_master_work_repos/odi_master_work_repos.htm
http://www.oracle.com/webfolder/technetwork/tutorials/obe/fmw/odi/odi_11g/odi_master_work_repos/odi_master_work_repos.htm