I live alone, so I swear constantly whenever I’m pissed off about something. I’ll also swear in the car (to myself, not at other people) whenever somebody does something particularly dickish or spectacularly stupid in traffic. When I’m in public, I keep my language clean, unless I’m with people I know whom I know won’t be offended by my cursing. Usually those people are also comfortable using profanity around acquaintances. I can switch the cursing on and off like that. I also have no reservations about invoking the name of God. I have no fear of divine retribution when it comes to things like that.
I am a wordsmith, so I only use words when they are appropriate. If the situation calls for it, I’ll use it.
I tried never to use certain words to apply to people. I once worked with a young rapper-type guy with a mouth to match the best of them. When I slammed down the phone one day and screamed “YOU BITCH” his mouth just dropped. He finally said “You don’t use that word.” “Sure I do. When it’s appropriate.”
Rarely enough that other people notice when I do but regularly enough that I don’t think of it as a line I step across. As Annie-Xmas says the words get used as appropriate. The key is deep breathing to ensure that they aren’t appropriate all the time.
Mad science, obviously. You don’t think Michael Jackson is really dead, do you?
Yep. Definitely going to hell.
My current assignment has a young lady in the warehouse who swears too much, in my opinion, which is odd, because I’m not prudish at all about swearing. Something about the way she does it comes across as extremely vulgar to me. Then it makes me wonder if I sound that vulgar when I swear, and I resolve to try to cut down on the cusswords a bit. Then I drive home, and my resolve goes out the fucking window.
At almost 44, I still try not to swear around my Mennonite mother - she really doesn’t appreciate it. My younger sister has earned the nickname Curser, the Potty-Mouthed Reindeer; Mom really doesn’t appreciate her swearing. 
I almost never use curse words, so when i do, people pay attention.
They also know that if they happen upon me mumbling under my breath in Irish, it’s a good time to back slowly away from the office door. . .
I make no special effort not to cuss, but it’s not as though it’s a constant urge that has to be battled at every turn. I’m very frequently neither cussing nor trying not to cuss.
So how do all of you who cuss in foreign tongues do it?
I speak quite nice Portuguese and own a very thorough hardcover book on Brazilian slang, with the vilest of phrases.
…but…
The Brazilian bad words just don’t have the required punch for me. If I’m going to let loose with a string of profanity at a balky printer or a wrench that is about to be thrown across the room, those words had better be richly imbued with feeling. And it has to be my mother tongue.
Of course, if I were to whisper even the lightest of South American expressions within fifty yards of my wife, I’m sure she would look on in shock.
In this sense, swearing is kind of like doing math: it’s a lot easier in your original language.
I work at a fucking restaurant. Of course I fucking swear. I don’t try to swear, but I don’t try not to.
My language is the Air Force dialect of Army Creole, with a dash of added salt that comes from working at a restaurant for years and years in the city.
Depends on the context. With my wife in Spanish, I swear because it’s fun to swear in Spanish. When I’m with her conservative family, it’s not so fun. When I’m at work with my American male engineers, swearing is de rigueur. Well, until those engineers are three salary grades above me, in which case is becomes the opposite of whatever de rigueur is in English. And swearing in German is funny to me, but not funny to Germans because apparently I’ve learned the vocabulary of 1970’s German.
I’m pretty liberal with the f-bomb. Sometimes it comes out in front of the kids and then my BF shoots me a dirty look. Like a lot of people, my cussing is in it’s finest form when I’m driving. Or when I’m trying really hard to do something. I think my best (and most often used) phrase is “G-ddamn piece of shit bitch”. Although I have to say I picked that one up from my sister.
I gave up swearing for Lent a few years ago and found myself shocked whenever I heard someone else doing it.
After no swears for a month I felt self conscious and got into the habit of whispering all of my foul language. Turns out a good fuck packs a mean punch when you do it really quietly. 
I had believed the terms to be mutually exclusive.
Back to the OP: All the fucking time.
From the Twitter feed Shit My Dad Says -
Ha! That’s where I don’t swear, I’m more like “come on baby, you know you want to …” I’m kind to inanimate objects, it’s people and situations that get it in the neck - cuntstantly.
I never waste an opportunity to observe “what a fucking cunts trick”
I swear when I hurt myself or am extremely angry.
Profanity is the last refuge of inarticulate motherfuckers.
There’s a difference between angry-swearing, humor-swearing, and swearing to add emphasis. I do all three with regularity. Racial or any-gay language, never. That’s a hanging offence around here.
There is one vocal habit I’ve been trying to break for years. For some reason, I started using ‘Cunt’ as a general-use, non-targeted curse word. (Alternatively, I use it to remind myself of the good in life when under stress . . . ok, I’m not buying that one, either) That is going to get me into bad trouble someday, unless I can stop it.
Especially considering I’m now working in a women’s college . . .
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I try to say odd, quirky things under stress, but they never occur to me until too late.
As do most, I select my vocabulary to match the audience. I watch my language around the kids, behave cautiously around strangers and authorities, and let my guard down with friends. When I’m driving, anything goes: blasphemy, vulgarity, profanity, and my most creative insults:
“Great greasy Jesus fuckin’ Christ on a balsawood crutch, you brain-dead cunt, pick a fuckin’ lane, already! You see the fuckin’ lines on the road, neanderfuck? They’re there for a REASON, you…oh, what is that, a Jesus fish? You shit-sucking son of a syphilitic weasel, take your goddamn fish and shove it up your ass! Fold it all corners and shove it all the way up, with Dave’s Atomic Habanero Salsa and your limp dick and a splint, motherfucker!”
I don’t call people “cocksucker,” though, 'cause there’s nothing wrong with that. And in the example above, the target is a man, 'cause I don’t call women “cunt.”