I know the first rule: Wear gloves when working with sheet metal!

Other than that, how hard is it to bend a strip of aluminum or thin
steel into a usable cookie cutter? Do you Super Glue the joint, or use
Pop rivets? (I don't have a spot welder) Maybe glue and 1 rivet.

I'm thinking of try it, using a strip cut from the top of a can -- with
the rolled edge intact, but that might make it too difficult to shape.
It would be nice if I could get away with leaving the seam welded and
not have to fasten anything, but that'll probably make shaping it a
*lot* harder (unless I just want a circle, or maybe an egg-shape)

I want a "dog bone" shape. Yeah I can just buy one, but that's not the
point. I need stuff like this to do in winter to keep me from going
crazy when it's -25°F outside and windy.

The puppy chewed my plastic cookie cutter and ruined it. :/

Bob