While on your way have lunch at Mangan village (ask your cab driver to make a stop at a good restaurant) and the scenery from the village is breathtaking. There is mostly vegetarian food but for all the non-veg lovers trust me the ambience, scenery and the atmosphere will be so soothing you won't be bothered about the good, nevertheless the food is quite tastily too.
You reach Lachung during the evening when it's mostly cloudy and dark as dusk hits so there's nothing much to see around just enjoy the quietness, calm and serene atmosphere and may be enjoy a few drinks to keep yourself warm as Lachung is located at an impressive height of 8858 ft.
It is the next morning that'll surprise you the most. Wake up early, as early at 4 a.m. to witness then stunning sunrise and suns rays cutting through the mountains and illuminating the surrounding forest area and Lachung Village. This will surely be one the highlight of the trip.