Introducing a helmet strap
One of the most enjoyable tools in ZBrush is the Insert Meshes. I love dragging on all kinds of junk, just to see what enhancements I can add to my characters. I go to Brushes and choose IMM Curve, then I press M to choose a belt to drag onto my character. Once dragged on, I click and drag onto an open section of the canvas to merge the belt with the face.