Place it somewhere public that you frequent and every time you pass it with your camera, take another photo of the same scene.
The next phase of this project will be to map the sites and allow others to take the same picture and upload them to a public gallery.
I love stopframe!
Step 1: You Will Need
4 x Cable ties
1 x 6mm bolt (I use 20mm long bolts)
2 x 6mm nuts
something to make the thing stick (options later on)
As you can see, it's not a complex thing we're making, so there are any number of mods you can make, depending on where it is going to be installed.
Step 2: Attach 2 Cable Ties
If you are going to bolt / screw / tie the thing onto something, skip this step.
Step 3: Attach the Bolt
Step 4: Attach the Means of Securing It to Things
If it's a street pole, use cable ties as depicted.
The rubber bands are to stop it slipping, but you can use anything appropriate. (see the pics)