When I was a kid we used to carry our worms in an old coffee can or one of the flat type tobacco tins that would fit easily into a pocket. If we were going to carry crickets, grasshoppers, roaches, or some other type of bug we made what we called a cricket cage. This was a simple device made of stuff from around the farm.
First we cut a couple of discs of wood out of a dried pine limb.
Then we drilled a hole in one of the pieces and banged a couple of fence staples into it.
Next we took an old piece of screen wire and tacked it around the two wooden discs.
A strap of leather or cordage was attached to the fence staples so that the cage could hang over our shoulder, and an old cork was used to plug the hole. That’s it. Plain and simple country engineering. Just gather a few bugs to go in the cage and head out for the pond. All that’s left is to catch some fish.