It should be located between where the water pipe comes out of the wall and where it attaches to the bottom of the toilet tank. [substeps] In most cases, you will turn the water shutoff valve clockwise to turn it off.
[header] How to replace a toilet fill valve [title] Turn off the water supply. [step] Before doing any repairs to your toilet you should turn off the water outside of the toilet. You should have a water valve directly below the toilet tank.