Great question — answering as the UphillTech team:
If you have access to the rooftop of the lower section of roof, you can climb on the roof and access the gable from above. Using clips (e.g.: Walmart ) you can subsequently use a pole to place and remove lights. When walking on a tile roof, walk on the peaks of the tiles to reduce risk of damaging them. Obviously care should be taken to not slip and fall off the roof. Maybe this year you can hire a light installing company or a handyman to install the clips.
Full answer by Arluin: https://diy.stackexchange.com/a/128177 (CC BY-SA 3.0).
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