To make an incredibly inept attempt at something with little or no forethought or experience.
I always thought, when I was a child, that one day I would wake up and miraculously have all of life's answers, but as I have gotten older I realize how badly my parents fumblefucked their way through life!
A discombobulated, uncoordinated idiot who runs into crap and can't hold onto anything, physically or mentally.
1. "He's such a fumblefuck..."
2. "Heylo, my name is Darius Fumblefuck."