This post is about what clothes I'll be wearing on the PCT, and how I'll be caring for them and avoiding thru-hiker stink.
Most of the time on the PCT I'll be hiking in shorts. I have black (unfortunately) polyester running shorts (unfortunately, black) with pockets on the sides. They dry extremely quickly and rarely need more than a few rinses and squeezes to get them "clean."
I'll have with me just one pair of synthetic underpants from ExOfficio. They are comfortable, dry quickly, and I can go without them for several hours as they dry. Rinsing and squeezing is often enough to clean them and takes just a minute, but a bit of scrubbing -- with or without soap/shampoo -- is sometimes necessary. These will need a rinse or wash on an almost daily basis.
I was initially planning to wear my thin Golite polyester shirt, but it develops a slight stingy smell after the first day of use that is almost impossible to remove. Wishing to avoid thru-hiker stink, I've decided to switch to the Icebreaker superfine 140 Tech T, made of merino wool. It weighs about 150 grams in size L. I know from experience that this fabric stinks up very slowly if ever. When it does need more than a rinsing, shampoo works on it much better than, say, Dr. Bronner's soap (after all, wool is a hair).
Actually, much of the time I'll be hiking shirtless to keep cool. I'll be protected from the sun by my Golite chrome dome umbrella. I'll be sweating less and drinking less water with the umbrella.
I have a complete wind layer, including hooded jacket, that weighs 200 grams in total. I'll be wearing this in cooler weather, when it's very windy and not hot, and when I want to protect myself from flies or poison oak. These can be sufficiently cleaned by rinsing and squeezing, and do not stink up in my experience.
I've been debating what to sleep in -- a silk bag liner, or a set of clothes that covers my whole body. If I don't sleep in some extra layer, my down quilt will get very soiled over time. The silk liner is obviously the lighter option, but slipping that on and then trying to enter my hammock will be a difficult feat. That means some sort of long underwear-type layer, which also doubles as hiking clothes for cooler temperatures. If I wear these on the trail, I should try to make sure I have my wind layer on top to keep the dirt out of them and keep them clean for sleeping.
I'll probably end up taking my Icebreaker merino wool: 150 weight leggings, and Mondo 200 zip long-sleave shirt. Together these weigh 400 grams and will probably be my only insulating layer. These will almost never require washing. If I switched to a capilene top and bottoms, that would only weigh 250 grams, but I think I'm hooked on merino wool. I think it will provide better insulation, as well (which I might or might not actually need).
I'll have lightweight and warm possum-down gloves from backpackinglight.com. I love these, but some people complain that they are not durable enough. If you'll be using them with trekking poles day after day, these might not hold up.
I also have a pair of Event rain mitts from mountainlaureldesigns.com. I will probably carry these all the time, because they double as bug mitts.
I'll be carrying just a Golite visor over a moist bandanna (which I'll pick up at ADZPCTKO) for sun protection when I can't use the umbrella for some reason.
For insulation, I'll have a very handy $1 fleece headband and a hooded wind shirt. For very cold conditions I can use the down hood that I use with my Jacks R Better down quilt. I doubt this will happen often.
I will probably try out a couple Walmart nylon dress socks early on, but I'll have a couple merino wool socks as well. I have some Smartwool socks to use up and expect them to develop holes after 20-40 days of use. Then I'll probably switch to Darn Tough socks, which are supposedly much more durable. If the nylon socks turn out to work best, then I'll have some more of those mailed to me.
For parts of Southern California and all of the Sierra, I'll be carrying Integral Designs vapor-barrier socks. These keep my feet dry and warm when hiking through snow or constantly wet trails. I have tried gore-tex socks, but they seem to stink up over time. Nylon can be washed more easily, and the warming effect seems greater.
Socks will require regular rinsing and squeezing and just occasional washing. Shampoo is best for merino wool.
If I feel I need more insulation for the Sierra or Washington, then I will choose either my Montbell UL down vest (160 grams) or backpackinglight Pro-60 parka (~350 grams). The second is a much better choice for cold, windy, and rainy conditions, while the first is greater as an additional layer in dry conditions.
Also, my Jacks R Better Rocky Mt. No Sniveller quilt doubles as a "serape" and can be worn around camp. It's generally not that practical to hike in, though (only in emergencies when it is not raining/snowing).
Clothes washing summary
To sum up, I can expect to be rinsing out socks and underwear on a daily basis, and two or three other items (shorts, shirt, windbreaker) about once per section. That's not too much work, and should be enough to keep me from getting stinky. Of course, they say that after a while on the trail you can't smell yourself anymore :)