Cleaning Grout|fast tips
Cleaning grout can be a tedious task; one trick I have used in the past is to spray the grout after a shower using a homemade mixture of bleach: Dilute the bleach with water 1 part bleach to 3 parts water before cleaning with it. Bleach is especially good for removing mold and mildew. It kills the mold and disinfectants too. It also removes stains and discolorations from white grout. Do not use beach on colored grout it can discolor the grout. Be careful when using bleach and any other cleaners, never mix cleaning chemicals especially those containing ammonia.
I also keep a plastic squeegee in the shower and do a quick squeegee of the walls and door to reduce the amount of hard water staining on the tile and grout.
Another quick option is to buy a Grout Pen which basically paints on a color to replace the dirty looking grout, but you have to clean first anyway before you can color the grout.
Cleaning grout can be a pain but by doing some of the work on an ongoing basis it can make the task easier.