Eyeshadow is the step most people abandon in their sixties and seventies, and the usual explanation — that it does not suit older eyes — is wrong. What has happened is that the lid changed shape and the technique did not.
Two things change. The upper lid loses elasticity and the brow descends slightly, so the fold of skin above the crease now sits lower and covers part of what used to be the visible lid. And the surface develops fine texture and crepiness. The first change breaks the placement; the second breaks the finish.
Why placement breaks. The method everyone learned is to put a mid-tone in the crease and a light shade on the lid. On a lid that has hooded, the crease has folded underneath the overhanging skin — so with your eyes open, the color you carefully placed is not visible at all. You see your own shadow doing nothing, conclude that eyeshadow does not work on your eyes, and stop. The fix is to place color slightly above the natural crease, where the overhang does not cover it, which means working with your eye open rather than closed.
Why finish breaks. Shimmer and frost particles are reflective, and on a lid with fine lines and crepiness they collect in the texture rather than lying flat across it. The result is sparkle sitting in lines, which emphasizes exactly what you were not trying to emphasize. Matte and satin finishes diffuse light evenly and do not do this.
And one thing worth saying plainly before the steps: on a mature eye, a defined lash line and a filled brow do more than lid color does. If eyeshadow is the part that frustrates you, it is the part to drop. Shadow is optional; the lash line is where the return per minute is highest. The eye-color shade guide covers which shades to pick, and the hooded eyes page covers the lid-shape question in more depth.