Cut sheet metal in half?
If you were doing a lot of freehand sheet metal work, I would recommend a nibbler (it takes little bites out of sheet metal) or set of powered shears with two cutting edges (they literally create a single thin strip of curled up waste material — my Milwaukee shears create a curled strip about 1/4” wide).

A band saw would be another option if you have one and it is large enough for the size of sheet metal strip you want.

A jig saw or sawzall with metal cutting blade and the sheet metal very well secured to an appropriate work surface might be the best diyer-friendly option if it is something you only need to do a couple of times and you already have one of those types of saws.