Rotate box

I am a bit lost with rotations of a box in the 3D world (Transform 3D). What I wanted to do is to have a vertex of th e box pointing directly towards the viewer so that the outline of the box is a regular hexagon with the vertex in the very center of it. I almost managed to position it as I wanted but only through an empiric way while I am wishing to understand the mathematical background of this kind of rotation…