Best hand tool to use to cut sheet metal (aluminum diamond plate)?

[Elgin Clock]

I'm sure this has been asked before, but I did search and didn't come up with anything yet.

Anyways, I have some sheets of aluminum diamond plate (slightly used) that I need to cut that are about 1/4' thick.

Some of my cuts will be just to trim some off of the sides the whole way down the ~4x8 sheet, but other cuts will be angled so the piece looks like a rather large triangle shape.

I can lay out a wooden jig to follow (instead of just a line with a sharpie drawn on it for a bit more accuracy) but my question is, what kind of tool & blade do I need?

I want to buy a circular saw anyways, but if I used that what kind of blade would I need?

We've cut metal before on a table saw for the team but I don't have access to that until build season, & I want to get this project finished over the fall/winter time.

Any help would be appreciated. Thanks!