I swear pretty regularly but can filter myself in certain situations pretty easily.
That said, I think taking offense to swear words (or, indeed, the concept) is among the stupidest humans have en masse. Lark called them "words of hate", but that isn't true. Words without context aren't hateful or loving. Even seemingly good words can be used to cut someone apart, and I'll bet most of the swear words you hear aren't used that way, at least not among friends, and if they are it's all in fun. I don't see a difference between saying "fuck" and "shoot" after messing up, or "shit" and "crap". They have the same meaning, the only reason one is more offensive is because you decide it so. I find the fact that swearing is so contentious to be a problem more among those taking offense than those swearing. A swear word, especially when not used to insult, does not hurt anyone unless someone, totally illogically, decides it hurts them. So as far as I can tell, it seems like they are more forcing themselves to get offended at nothing than really being offended.
And it absurd, for example, the King's Speech was rated R solely because the main character says fuck five times, in a story-relevant way, and not directed at any other character nor used as in insult. And the fact that, when they cut three of them, for some reason now it's inoffensive enough to be PG-13. It's fickle, absurd, and to me it's telling of the entire weird attitude the nation has towards words like that.
Of course, there are a few words that are, inescapably, words of hate. And those words I never, ever say. These words are racial slurs and slurs against people of different beliefs or sexual orientations. I don't even call things "gay" in a derogatory manner as is so popular nowadays. I find THAT to be hateful (I mean, if it were well known that back in the 50s people used the term "black" in the same way, we would think it was terrible).