I take it as obvious that signaling is an important function in many human behaviors. That is, the details of many of our behaviors make sense as a package designed to persuade others to think well of us. While we may not be conscious of this design, it seems important nonetheless. In fact, in many areas we seem to be designed to not be conscious of this influence on our behavior.
But if signaling is not equally important to all behaviors, we can sensibly ask the question: for which behaviors does signaling least influence our detailed behavior patterns? That is, for what behaviors need we be the least concerned that our detailed behaviors are designed to achieve signaling functions? For what actions can we most reasonably believe that we do them for the non-signaling reasons we usually give?
You might suggest sleep, but others are often jealous of how much sleep we get, or impressed by how little sleep we can get by on. You might suggest watching TV, but people often go out of their way to mention what TV shows they watch. The best candidate I can think of so far is masturbation, though some folks seem to brag about it as a sign of their inexhaustible libido.
So I thought to ask the many thoughtful commentors at Less Wrong: what are good candidates for our least signaling activities?
Added: My interest in this question is to look for signs of when we can more trust our conscious reasoning about what to do when how. The more signaling matters, the less I can trust such reasoning, as it usually does not acknowledge the signaling influences. If there is a distinctive mental mode we enter when reasoning about how exactly to defecate, nose-pick, sleep, masturbate, and so on, this is plausibly a more honest mental mode. It would be useful to know what our most honest mental modes look like.
As others have mentioned, there seems like there's an important distinction between doing things, talking about doing things, and doing things so we can talk about having done them. Whether or not they actually signal anything is a different issue. There are many things I think we do or do not do with no signaling intent. We sincerely might not care what our shoes say about us, and so our choice of shoes has very little signaling motivation, but we may nevertheless signal very strongly to certain people through our choice of shoes.
And many things that we do not intending to signal, we can use to signal by talking about them later. Like everybody, I need to eat. I used to go to lunch at the same place every day and get "the special," since it was always one of three sandwiches I liked, and that way I didn't have to think about it. At some point, it occurred to me that telling someone that I ordered "the special" every day might communicate something like my highly-focused intellectual's dislike of trivial distraction, so I started to tell people that I ordered the special for lunch every day. But that's not why I started doing it. I now eat a ham sub sandwich almost every day for lunch, and I don't believe I have told this to anyone before now. No doubt I signal something when I say that I do this almost exclusively because I like ham subs from this particular shop a lot and it doesn't cost very much, but I don't eat there all the time so I can say this.
Like others, I like to impress people with how impressively well-read I am. For all I know, all my intellectual interests are rooted in some kind of biological signaling imperative. But given those interests, I read lots of things just because I'm curious about them. There's lots of stuff that I've read in private and never thought about again. Same with TV. In fact, these are probably my main non-signaling activities, time-wise. That said, I read even more stuff because I want to draw on it in conversations and debates, etc. We might choose to undertake certain KINDS of conventionally strongly signaling activities in order to signal, but we might also perform the activity in specific instances with no signaling interest.
Also, cuddling and playing with my dog. I do it a lot when nobody's around because I really like it. Maybe I'm signaling to my dog that I love him? Maybe certain kinds of signaling are enjoyable for their own sake, and so we send the signals to our dogs or into an empty house, indifferent to its success, just because we need to send signals like we need to eat?