The most common way to identify that a sink drain is clogged is by the water that backs up into the sink instead of running down the drain like it usually does. When you see that a sink isn’t draining, it’s time to start going through the steps necessary to clear the pipe.
Many kitchen sinks are equipped with an erator that grinds up food that would otherwise clog your drain. If your sink is backing up and you have an erator, try simply activating it to clear the clog.
Use the Plunger
If your sink doesn’t have an erator or if it doesn’t clear the clog, the next step is to use the plunger
Clear the Trap
If plunging doesn’t clear the clog, it’s time to remove and clear the trap.
Put it Back and Test
Once you’ve cleared the clog, it’s time to re-attach the trap and test your work.