I just received my wand and noticed a horizontal line on the wand about an inch from the bottom. Is this a depth mark of some kind? I searched the videos for instructions on how to use this particular wand but no luck. Would you have some tips?
There is no "proper" depth marking on the wand. It is really all a matter of practice. Mark and Morgan recently did a video about the different Gaggia wands that I think you may find helpful: