The act of assembling any newly obtained product without the aid of the included instructions. Usually performed by men who feel they don't need mundane advice from a useless piece of paper, this can result in time delays during construction.
Ego Man #1: Nah, we don't need the instructions to assemble this new set of storage shelves - instructions are for lames, dude. We'll use our built in manstructions.
Ego Man #2: Damn strait man, hell yah - lets do it.
~5 hours later~
Ego Man #1: Sh*t we should have used those instructions.