0 (in football) the act of hitting the ball with the head -- cabezazo
He scored with a great header.
1 a fall or dive forwards -- salto/caída de cabeza
He slipped and took a header into the mud.
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
Podemos completarlo paso a paso, por muy largo que sea el camino, y no se puede completar, por corto que sea el camino, si ni siquiera marcas tu huella.