Participants have to make their own arrangements for their accommodation.
Notice that the main CERN entrance is in Switzerland, while some of the suggested hotels are located in France. Public transportation from locations in Geneva, Meyrin or Cointrin is efficient, but not from hotels located on the french side.
On general grounds we recommend hotels in downtown Geneva (unless you have a car). A convenient area to connect with public transportation to CERN is the Cornavin train station, which is also close to the city center.