Recently a reader asked me how I possibly got my pack down to 8.5 KG (just under 20 pounds) including water and I realized that I have never really gone over what I pack when I go trekking in the Himalaya. That said I'll take this opportunity to correct that oversight and go over some basic things I do and bring to keep my pack weight down on the trail. Of course there is some variation on what you will bring depending on the season, if you need cold weather gear, or if you actually need a sleeping bag because of the scarcity of blankets due to peek season. What follows are mostly general rules of thumb. I am not one of these ultra light people who spend more time on forums discussing the advantages of drilling holes in your toothbrush to reduce its weight than actual trekking, I try to strike a decent balance between comfort and getting my pack down to a manageable weight that has minimal effect on slowing me down on the trail.
Rule # 1- pack end of the day clothes in a separate watertight container like a Sea to Summit bag. This is the biggest luxury I afford myself on the trek, I always pack one set of clothes that I never actually wear while trekking and they never mix with the sweaty dirty clothes that fill the rest of my bag. I find I can trek through any conditions as long as I know at the end of the day I have something I can change in to and feel like I'm something resembling a civilized human being. This set of clothes includes one pair of comfortable socks, lightweight synthetic pants like wind pants or imitation zip offs, a tee shirt, light weight fleece, and a pair of boxers.
Rule # 2- Packing lots of clothes is silly. Cotton clothes suck, don't ever pack them as they are heavy and never dry once wet. Never trek in jeans- really just don't do it, they are stupidly heavy, never dry and chafe like cheese grater. Bring lightweight wicking synthetics. They don't weigh anything, and they dry quickly. If you can, invest in underwear of this sort as well, I get mine from EMS and highly recommend them as it cuts way down on chafing, they dry quickly and keep you from getting crotch rot. Most importantly something to understand is that having lots of different outfits is counter productive on a trip that lasts more than a few days. Once you have lots of dirty clothes you're just carrying around laundry. As a general rule I carry one extra set of clothes in my pack and one set I can wear on the trail so that I can always be wearing one while the other dries on the back of my pack or whatever. Underwear and socks are the slight exception and I do bring one additional pair of wicking boxers as well as two additional pairs of socks. For socks I really love the very thin lightweight cool max ones and usually bring three pairs as well as two pairs of smart wool thicker socks if I think there will be cold conditions. For thermals I bring a set of top and bottom silk underliners which are absurdly light and provide great warmth. additionally I pack one light fleece, a windbreaker/rain shell, and possibly if it's cold a light weight down jacket. I only recommend the jacket if you are trekking in the winter months as most often it makes you sweat far too much to be worth it.
Rule # 3- Use a Camelback. Yes there was a time when I thought they looked stupid too, and I've had people ask me if I'm getting oxygen from it, but these things are by far the best way to carry water. For me I like to settle into a nice rhythm when trekking that is not so fast that I need to stop too often...in fact I hate breaking my rhythm so I love not having to stop to fish out a water bottle. Most importantly by hanging the water bladder right next to your back it is in a place where one of the heaviest components in my pack is in a place that feels the lightest. If all that weight were out on the edge of my pack for instance it would create a certain amount of torque that would feel heavier as it moved around. Best to have it nice and close to your center of gravity. I carry a 2.5 litre bladder in my pack and supplement this with a one litre Nalgene bottle. That's a lot of water weight, but I hate stopping for water on the trail, and your pack gets lighter as the day goes on. I don't always fill the Nalgene bottle when on the trail, as I mostly use it as an end of the day bottle for drinking and brushing my teeth. I do however include it as full when weighing my pack.
Rule #4- Minimize Extras. Lots of people bring a book, and that's cool, I bring my Kindle. What you don't want to do is bring a library with you, or a 900 page tome. If you're just doing one of the main tea house treks in Nepal you don't need fancy ice axes, trekking poles are over rated (IMO), crampons, tents, sleep pads, cook sets, etc. I've never brought a sleeping bag and rely only on a sleep sack (silk), if I even bother bring that. What you need to remember is that every day you end in a village usually. You get a bed, someone else cooks for you, they have blankets, etc. In peak seasons (I've never been during peak times- always go on the cusp) I've heard that beds can be scarce and blankets sometimes run out. In this case by all means bring something else, but really I'd just recommend avoiding peak season. Carry emergency food like some chocolate, nuts, or dried fruit as well as something to make the monotonous servings of starches in the form of potatoes, rice, or noodles edible (I recommend a small bottle of Tobasco), but don't get carried away and bring freeze dried meals, jars of peanut butter and the like.
Below is a typical packing list of what I have in my pack-
(not included are the items I'm wearing)
-End of the day bag (described above)
-2 pairs of coolmax socks
-1 or 2 pairs of smart wool socks
-2 pair of wicking underwear
-1 Lightweight synthetic zip off pants (can become shorts)
-1 long sleeve Polartech shirt
-1 Short Sleeve wicking shirt
-1 Silk Thermal layer (top and bottom if it's going to be cold)
-EMS Techwick fleece
-Pearl Izumi Windbreaker/Rain Shell
-Fake polartech headband thing that covers my ears if it gets windy and cold
-Silk sleep sack
-Sarong (I can use this as a make shift blanket, a lightweight towel, etc.)
-Bag with documents- TIMS card, wallet, passport, park entry, phone, etc.
-Aquamira Water Sanitation drops
-Case for my glasses/sunglasses and contents
-Pair of Sandals
-2.5 litre Cammelback Blatter
-1litre Nalgene bottle
-Small bar of Dove soap (leaves far less residue in your hair than other brands)
-Toothbrush/small bottle of toothpaste
-Pills (advil, cipro, Imodium AD)
-Chocolate Bars (2)
-Small bottle of Tobasco sauce
-Olympus pocket camera (waterproof/drop proof)
-Garmin GPS device
And that's roughly it. At the end of any day I try and wash myself up, if the temperature allows for it, as well as the clothes I was wearing and hang them out to dry. If I was crazy in to going lightweight I could even cut this list roughly in half, but I find that reducing my pack weight further doesn't make life that much easier on the trail. I've used roughly this list for my last four hikes and I haven't hit a snag yet.