If you have dirty marks on your mirror or finger smudges, then follow this guide on how to make your mirror clean without needing to use any chemicals, and only using water:
1. Take a PVA Microfibre Cloth and dampen it with water, but make sure to thoroughly wring out the excess water, otherwise this cloth will not perform as well compared to when it is damp.
2. Once the cloth is just damp, wipe over the dirty marks and finger smudges on the mirror.
3. To start, the PVA Microfibre Cloth will leave smears on the mirror, but within seconds the smears will disappear leaving a crystal clear appearance.