Of all the elements of home repair, grout should typically be invisible. If you're noticing it, chances are it was either applied too thick or it's sporting a coat of mold or mildew. If you reevaluate your home repair project and notice the grout, not the tile, dissolving extra grout will get you that clean-cut look and showcase your tiles.
Gather all your tools. Pour some warm water on the tile to protect its surface while you begin to dissolve the grout.
Run your oak strip over the grout, working back and forth along a straight line. The top layers of grout should come off the tile onto the stick. If the end of the stick gets too gunky, wipe it off with a towel then get back to work. If the end gets too blunt, flip the stick around to get the other side. Keep working with the oak stick to dissolve as much of the grout around all your tiles as you can. If the tile dries off, re-wet it.
Rinse off the tile with warm water when you finish working with your stick. By now, the tiles should be free of some excess grout, but you can still dissolve more for a neat look.
Wet your nylon scrubber, and wet the tile again if it is not wet. Draw the scrubber back and forth over the grout and tile to dissolve it. Because the nylon scrubber is soft, you can draw it over the tile without scratching it.
Stop scrubbing when you've removed enough excess grout and the tile looks good. Rinse the tile once more.
Dry your tile with a soft towel, then inspect it again. Wet tile may look clean but still have a grout haze. If you notice your seems hazy when dry, re-wet it and get back to scrubbing until the tile appears clean when dry.