Attach the magnetic hooks to the ferromagnetic surface at the required intervals and then place the chain of lights on the hooks as desired. A clever solution that does not require drilling, nails or adhesive tape.
During inclement weather the fairy lights could slip out of the hooks and be damaged. For safety reasons we therefore advise you to remove the fairy lights in such situations.
TIP: An alternative to magnetic hooks is the adhesive putty Sugru. Form hooks with it and then attach them to the desired surface (plastic, wood, stone, etc.). Once the putty has dried, you can attach the chain of lights to the Sugru hooks.