The central theme of your site must be explored from all angles, above and beyond the Commission or the DG's structure, if it is to provide added value for the user. In relation to your target audience and the complexity of content, the thematic approach and paradigm of navigation will have to be defined.
The role of the site vis-à-vis the policy or activity in question should be decided. And the architecture as well as a map of the site should be drawn. Once available, the thematic site map should be submitted to the Editorial Committee of EUROPA and the Ceiii, if its character is interinstitutional, so as to make sure that the project does not overlap with other sites in preparation and that all relevant DGs are involved.
More links on organisational aspects in the Planning chapter.