Step 1:
Make sure that you have everything with you when you go into the area to be cleaned. Wet floors would become muddy if you keep on entering from outside the area.

Step 2:
Place walk-off mats at the entrance so that people who might want to come in can dust off their shoes or feet.

Step 3:
If the area is big or if you are cleaning the toilet and bath, plan your cleaning action properly. Dust off all the things that need dusting, as well as the ceiling. This way, you can avoid having to sweep and mop the floor area again and again.

Step 4:
Sweep the entire area of dust and debris for floors. For walls, backsplashes, or areas surrounding the bathtub, use water and a rag to clean off the surface.

Step 5:
You can use a vacuum to make sure all the loose dirt can be taken off. Make sure not to use a beater bar as this may cause scratches on the tiles. Some of the attachments though, will come in handy for hard to reach corners and in between fixtures.

Step 6:
Check for hard water stains near and behind water pipes, soap ****, and mildew stains. Check the recommendations for mixtures that can help you with these stains or you may choose to use commercial cleaning solutions. Make sure to read the label first to know if the product you will be using is appropriate for the type of tile you are cleaning. If unsure, especially with your own mixtures, choose a small and inconspicuous area to test the solution on. Let stand for 15 minutes and see if the solution works or if it discolors or ruins the tiles and grout in any way.

Step 7:
Textured tiles might require a little bit of extra brushing since they have more grooves to clean. You may also use an electric polisher for better luster and shine.

Step 8:
After you have cleaned the tougher stains, mop or wipe the tiles and grout and start working on the grouts themselves.

Step 9:
Brush the tile joints with a medium-bristled brush so as to avoid scratching the tiles. Again, check the above suggested solutions for grout cleaning. Wipe dry the tile joints.

Step 10:
Use your mop or rag and apply the cleaning solution of choice to the tiles. Afterwards, rinse the tiles and wipe dry. Warm water does wonders to any cleaning activity as it helps dissolve a lot of stains, grease and mildew.

Step 11:
Place a new walk-off mat at the entrance.

For more: How to start a cleaning business