Eye makeup is the part of a routine that depends most on close vision, and near focus declines for almost everyone from the forties onward. So this is a widely shared problem that almost no beauty publisher addresses, and the fixes are more practical than cosmetic.
Start with the conditions, not the technique. Three things determine whether you can see what you are doing: magnification, light direction, and whether your hands are free. Getting those right solves more than any product change, and getting them wrong makes every product harder.
Magnification. A 10x panel makes the lash line and individual brow hairs visible at a working distance. It is the single most useful purchase in this section and it is not a cosmetic.
Light direction, which is underrated. An overhead bathroom light casts a shadow in every downward-facing surface of your face — under the brow, under the eye, in every line. That both flatters badly and genuinely obscures what you are trying to see. Front light at face height, which is what an integrated mirror light provides, fills those shadows instead of creating them.
And a crucial detail about magnification: it dims. A lens spreads the available light across a larger apparent image, so a 10x view in a dim room is darker than a 1x view. That is why an unlit magnifying mirror disappoints, and why light and magnification have to arrive together.
Then — and only then — choose products that forgive imprecision. A brow gel needs one stroke in roughly the right direction. A pencil smudged into a shadow needs approximate placement. A cream shadow stick needs no blending judgment. All three give a defined eye without requiring you to see a fine line clearly.