Transport
Getting around Geneva is best done by public transport. Using a car is discouraged, but CERN does have parking space on site (please let the organizers know if you plan to come by car, in order to give you access).
The closest railway station is Geneve Cornavin or Geneve Aeroport, approx. 30 min from the CERN site by public transport.
The Geneva public transport agency TPG provides tram and bus services in Geneva; The final stop of Tram 18 is right by the CERN Meyrin Campus.
Planning your trip is easiest with tpg.ch or sbb.ch which combines all options.
Accomodation
There are many hotels in Geneva in a wide range of prices, but typically expensive. We cannot endorse any particular hotel, but would recommend to stay at the CERN Hostel.