Important stuff
Don't forget:
Clothes
When packing clothes minimal is best, first check the weather conditions to help you pack accordingly. You should pack dark colored clothes or patterned clothes as they don�t show up the dirt. Also you should choose outfits that can be mixed and matched so you have a variety of outfits. It�s a good idea to use space saver bags, they not only save space but help to keep your clothing dry, clean and crease free.
Footwear
Of course comfortable and well broken in trekking shoes are essential for Nepal, light sandals and a pair of comfortable trainers are generally enough.
Back pack
In Nepal, a back pack is more convenient than a suit case. If you plan on trekking, a sturdy and comfortable back pack and day pack is essential. You should have your back pack expertly fitted to you before your departure. Your back pack should also have a water proof cover.
Camera
What better way to record your memories than a camera? Please insure you bring along the relevant batteries/charger with an adaptor suitable for the country. Also you should bring along adequate memory cards/ film. These things are not available in trekking areas.
Others
Be aware of 20kg allowed in suitcases. Some things that you might find handy on your trip.