>>1920688Just to be clear, a winter sock is like a big bag that encloses your hammock and traps the warmth. It also stops the wind from stealing heat from your UQ.
I also recommend fresh, thick wool socks for when you go to sleep though. Only wear them when in the hammock. I bought my gf a pair of down booties from Dutchware that were pretty cheap and she seems to like them, so those are an option too.
My feet are the first thing to get cold as you can probably tell.
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>>1920694 said, layers are generally the key. You can also get a sleeping pad to help buffer your UQ; people have a lot of success with them, but I personally can't stand them which is why I went with the expensive 10ºF UQ.