We all know the classics. Asshole. Or perhaps you like to tell someone “to be fruitful and multiply, but not in those words.” Douche. Prick. I like some British ones. Git. Wanker. Bell end. Prat. Etc.
But what classics do you use? Ne’er-do-well. Villain. Rampallian. Vituperative. Pernicious. Pestiferous. Flibbertigibbet.
Most often I use, no good so and so or dumb-dumb, or silly idiot, or say that a fella has a real backpfeifengesicht (which loosely translates to a face badly in need of a fist). I don’t often swear. I find it more satisfying to confuse someone with awkward words (when’s the last time you heard silly used in an angry situation?).
note: I can never remember what flibbertigibbet means. It means a frivolous, flighty, or excessively talkative person. That annoys me every time.