From NJP you can get share car for Manebhanjan, It will take around 4 hours. From manebhanjan your journey to heaven will began. From Darjeeling, Manebhanjan is only 1 hour 15 minutes . So while coming from NJP/Bagdogra, most tourists prefer to stay overnight at Manebhanjan and then proceed for Sandakphu next morning. However from Darjeeling, there is no such issue of long driving hours and you can proceed directly to Sandakphu.