How to cut aluminium chequer plate (with a jigsaw)?
They do make blades designed for non-ferrous metal, and may make a difference over a standard bi-metal/multipurpose blade. These may be special order v. a home depot find.

I suggest going almost painfully slow to maximize cutting, over deforming the material/dulling the blade.

However, the two best ways I know to cut this material are a power 'nibbler' that cuts semi-circular bits out with a repeating punch style cutter, or on a power shear.