I'm no mathematician, but I'm fascinated with geometry, abstract shapes, angles, direction, movement. As you can see with quite a bit of my work, I want to capture abstractions that give the viewer a sense of direction, constraint, enclosure, balance.
But much of fine art doesn't require complicated tools. Other than brush, paint, and canvas, my "tools" are more household than high-tech. Plain masking tape (typically stolen from the stash in the garage) is my go to for marking off areas on a canvas. Scissors for cutting the tape (when a good tear-off isn't appropriate), utility knives for whatever. A sharpened stick to press down tape edges.
The tools that lend themselves to my own brand of graphic-design-influenced art are the large ruler and compass for measuring out simple grids and shapes – most designers will recognize the process of giving myself a framework to build on or break from.