Actually it’s pretty simple. Collect pre-war mountain of money that really are not worth in the Wasteland of Fallout 4. Put the money in the former container. Arm yourself with grenade launchers. Point it at one of the corners of a container and shoot. Enjoy the money rain in Fallout 4.
An example of such entertainment was provided by liftislyfe, which used 1270 packs of pre-war money.