Packing for a holiday in Nepal isn't to be taken lightly. You need to pack your case with care.
First of all, as far as clothes go, you'll need a little of everything. Light outfits for the southerly areas and clothes to beat the cold if you're going a little higher. If you're intending to go on a trek in the mountains, make sure you bring all the necessary equipment. It isn't desperately important if you forget something though, there are plenty of specialist shops where you can buy mountaineering gear. You'll find it in Katmandu or Pokhara in particular. This might be a simpler option if you don't want to carry too much and you prefer to buy everything when you get there. Trek or no trek, a good pair of walking boots is indispensable.
Your first-aid kit must be considered very carefully. Apart from basic medicines, don't forget something for tummy trouble, plasters for blisters and a remedy for acute altitude sickness. Include mosquito repellent and a high SPF sun lotion. On the subject of the sun, remember too to bring sunglasses and a hat. As if that wasn't enough, you'll also need an after-sun lotion to relieve sunburn.
As regards cash, use a bank card when you can, it's more practical than carrying travellers' cheques. There are ATMs in all the big towns. It's always wise too to take photocopies of your passport. This will be very useful if you manage to lose it. Obtain an international driving licence before you leave if you are thinking of hiring a car.
Lastly, don't go to Nepal without a never-ending thirst for adventure and an adventurous sprit.
NB. Following the two powerful earthquakes that struck Nepal in April and May 2015, the country is slowly getting back on its feet. This article was written before the disaster.