Buy a commercial cleaning cream. It doesn’t need to be expensive—a generic brand should suffice. Find a shower cream anywhere that sells cleaning supplies: home-and-garden stores, bathroom-supply stores, and some drugstores. Squeeze a bit into your hand or a cloth and spread it over the whole surface of the screen.
Don’t worry about ruining the surface—the cream doesn’t harm glass. Rub the cream all over the glass, and don’t feel that you need to rub too hard. If you have a marble shower, you should keep the cleaning cream away from the marble. Grab a damp/wet cloth and wipe off the cream. The cream will froth, and it might take a few attempts to wipe it all off—but you don’t need to scrub!
Dry the screen. Use a clean, dry towel (cloth or paper) to gently dry the shower screen so that the end result is evenly clean. Repeat the process for the tiles the tiles. If you’re worried about the surface of your tiles, you can put the cream onto a cloth instead, but it will take longer and more persistence.
Spray your shower screen with window cleaner and wipe with a squeegee. You can use any commercial window cleaner—for example, Windex. If you do not have a squeegee, consider using a sponge. First, rinse the surface. Get rid of any dirt that has collected on the surface of the shower screen. You can run water from shower over the screen to wash away dirt, or you can use an external water source.
Spray window cleaner on the surface, then lightly wipe it down with a paper towel. Squeegee the surface. Spray on another layer of your preferred window-cleaning solution, then go over the surface with the squeegee until it is perfectly clean. If there are any marks left after the squeegee, go over the surface with a dry paper towel. Don’t be afraid to scrub stubborn spots.