Check your water meter – Turn off all your faucet at home, check if the spinner rotates, If it does you have a leak on your after-meter connection
Check outside – Check your front lawn and outside pipe for hidden leaks
Monitor your water bill – Compare your previous water bill to your current bill, if your consumption is higher than your usual usage, this may indicate that you have an unnoticed leak on your in-house plumbing.
Grab some food coloring – Take the toilet test, add a few drops of food coloring to your toilet tank and wait for 10 minutes. If the color shows up in your bowl, then, you have a leak