Don’t overdo it. A sundae is not delicious if you put too many sprinkles on it. Treat obscenities like sprinkles. They should enhance, not detract from, the message you are sending. Use the words for emphasis. And only occasionally.
I actually never swear around the boys. I'm just not a big swearer in the first place, but it's more of a compartmentalized thing for me. After years of working in studios with hot mics, I learned not to swear in certain situations. When the boys were little, I treated being around them the same way. Their brains were the hot mics, ready to pick up words and broadcast them elsewhere. I didn't care if they knew the words; I just didn't want them to casually flop out some spicy language at my mom's house. Or at school. Or at church. Or really anywhere I'd have to see the judgemental glances of the easily offended.
Bridget and I never really discussed this, but I'm pretty sure I know her opinion about this too. Those words should only be used in the car, while experiencing road rage, the way God intended.