Lots of little hits will make your piece of metal take shape.
Cold forming sheet metal with a hammer.
These are bent out alternately and mated with the edge to be joined.
This takes patience and can be meditative.
This involves forming a feathering by hammering the edges of the sheet to about half their original thickness and then cutting slits at right angles to the edge.
Hammer forming is one of the oldest simplest and least expensive ways to shape sheet metal.
You want to put your metal over the dent and hammer it with the ball end of the ball peen hammer.
Move the metal around to get a smooth bowl shape.
This is a handy metal fabrication technique you need to learn.