Plumber is here and putting in the plumbing for the shower. I have a Grohe Shower Bar with a hand held shower head but there are no instructions as to where to put the pipe from the wall/ the elbow connection.

I thought it would be obvious but it's not because I don't want the shower head to be able to hit the floor or the hose to hand down over the corner bench seat. Any instruction or pictures I can show the plumber?