If you have luggage, then I think most convenient is taking bus from HND to Yokohama City Air Terminal. This bus has a under belly baggage space. Yokohama City Air Terminal is located in west side of JR Yokohama station right by Sogo department store, Fare is 650 yen per person, and bus departs every 10-20 min from Terminal 1 and Terminal 2. Every 30 min.-1 hr. from Terminal 3.

From Yokohama City Air Terminal, Hilton Yokohama is less than one kilometer in distance. If you get out on east side of Yokohama City Air Terminal, you can actually see Hilton Yokohama on another side of the river. Because of the river between Yokohama City Air Terminal and Hilton Yokohama, you cannot walk straight to Hilton Yokohama. You have to walk around and across the bridge to Hilton Yokohama. The walk will be still less than one kilometer, but walking with luggage may not be the best situation. Taxi ride from Yokohama City Air Terminal to Hilton Yokohama will be short one kilometer ride with around 500 yen.