pdcb
Go to the nearest train station they have an tourist information and they will tell you the best way to transfer on trains i am assuming that you are taking a train.

uhm101
Go to Put '河口湖' into the '出発駅' field Put '箱根湯本' into the '到着駅' field (you can actually type station names in romaji too) Select your date/time of departure in the next section and press the button.

Smg
take the bus route; Kawaguchiko => Gotemba => Gora => Hakone total; JPY 2830-/3h0m~3h30m Details Kawaguchiko Station => Gotemba Station Fuji Kyuko Bus JPY 1470- 1h10m departure time 7.35am ~ 7.00pm (every 30minutes) Gotemba Station => Gora Station Hakone Tozan Bus JPY 970- 0h50m departure time Weekday: 7.33am, 3.10pm, 5.20pm and 6.20pm Saturday and Sunday: 9.50am, 12.00pm, 3.00pm, 4.00pm and 5.00pm Gora Station => Hakone Yumoto Station Hakone Tozan Railway JPY 390- 0h35m departure time 5.25am ~ 10.39pm (every 20minutes) Weekday; Saturday, Sunday and Holiday; #

h.s.e
Here is some information in English.. # Search engines to check time tables, courses, and fares in Japan.