Depends on "whose" guidelines you're talking about. Federal, state, local, plus they change a bunch over the past year. Back in October when there was a decent lull and things were relatively safe, open, and lax, I may have made a little stop over in the mid west to meet up with some WAM ladies.
Not counting the 2 metre or 1 metre guidelines, as often other people will break that for you in a shop etc.
Other than that, just once. There was a ban on going inside a cafe/restaurant/bar with people outside your household (outside was allowed), and I met up with a couple in a cafe for an hour just before Christmas. But it's an open plan cafe in a large shopping centre, and so not really the same as a small pub or cafe as there's obviously plenty of air circulation.
Other than that, I've adhered to them as far as I know - although some of the rules have been a bit odd. I could go somewhere in a taxi, but not get in a car belonging to a family member, when I clearly know who has been in and out of that car whereas I don't with a taxi.
I've been following the guidelines the same way our elected Members of Parliament follow them.
After all its all very important that the rules are followed and taken seriously, and its good to know the establishment is leading by example by following their own dictates to the letter....
I was going to say: never. Absolutely never. Always wear my mask in public. But, then, I remember, I never wash my hands. Or barely. So, I wonder: does that break some guideline?
Most important thing I am doing: not breeding, not forcing another nonconsenting person into existence to suffer & die from Covid19.
The "guidelines" for my part of the world, Tennessee in particular, and the Southeastern USA in general, haven't been too severe so it's not a big problem. I was in DisneyWorld the week before they closed. We've been to Church regularly and traveled a bit. We observe reasonble precautions, just to be polite if no other reason, like most everyone else. Got together with family over the holidays. I'm 58 so hopefully I'll be able to get vaccinated by late March/early April. So far my family hasn't had any issues. Hope that continues.
I guess the real answer to the question is "some". Haven't gone out of the way to adhere to, or break, rules where they exist. Fortunately that's relatively easy here.