A method of attaching a line to a support structure includes providing a holder having a fastening section, a side-part section, a closure section, and an engagement section, where the fastening section, the side-part section, and the engagement section define a ring having a gap. The method further includes fastening the fastening section to the support structure, bending the side-part section with respect to the fastening section after the fastening section has been fastened to the support structure, inserting the line through the gap into the ring, and bending the closure section with respect to at least one of the fastening section, the side-part section, and the engagement section such that the closure section engages the engagement section and closes the gap.