While trekking in Nepal, you will have to clothe in layers. You should make sure that your inner layer is quick-dry, light, and has excellent breathability like synthetic t-shirts. Down or fleece jackets are a must, and the outer layer must be wind and waterproof. If you are trekking to the altitude of more than 3000 meters, you need to add more layers as it will be colder in higher elevations. Also, make sure to pack smaller items like gloves, towels, sunglasses, hats, light cotton inners, and scarves. As for trekking in lower altitudes, you will require one thin thermal and loose track pant or fleece pants. Comfortable hiking shoes and sandals like crocs are also necessary.