Just take a bus from the Airport and SBB station, although you have to pay about 3 CHF to get to the hotel, the hotel will offer you a complementary transport card for the return to the SBB station and for sightseeing in Geneva the next day. The airport is just 1 stop and SBB from Geneva Main Station. Hotel is modern and clean with air conditioning, but you can't lock the door of the bathroom. Breakfast is basic.