Where is the water shut off usually located?
Keeping this in consideration, where does the main water line enter a house?
Your main water supply line enters your home at ground level or below. In warm weather zones, the line usually sticks up out of the ground just outside the home and then enters the side of the house.
Also, where is the water shut off valve for a shower? This supply valve is usually near the bottom left side of the toilet tank. For showers/tubs, look around the tub or shower for an access panel. It may be on the other side of the wall from the tub or shower.
Keeping this in view, how do you turn off water supply?
The shut-off valve for your home's water main is likely located in the basement, near your water meter or wherever the local water supply enters your home. Generally speaking, it will be on the wall that faces the street. If this shut-off valve is tap- or knob-style, turn it clockwise (to the right), to turn it off.
Is it safe to turn off main water supply?
Turning off your main water supply during vacation is a smart way to avoid unexpected flooding while you're away. You should turn off the mains water supply when you're away from your home on vacation, even for short weekend trips. This keeps your home safe from flooding while you're not around.