I drew out some rounded diamonds in Inkscape and then articulated them to one another. I made a set 25% larger and added in some varying stem lengths. These are adhered using remountable spray adhesive (3M) and they leave no trace on the wall. They do occasionally fall off, I just spray a bit more adhesive on them and slap 'em back on.
I had originally intended this design for a birthday card, but never quite managed to make it. Instead it became a reminder of air travel and the possibility of what could be when leaving the house. These were scraps from my projects. The sky-blue is card and the navy is standard paper weight.