Use baking soda, vinegar, salt, and boiling water.
As an alternative to a liquid plumber, combining baking soda and vinegar can be very effective. Pour baking soda down the drain first, then pour vinegar to cause the fizzing chemical reaction. This helps to loosen debris in the way as it expands. Let it sit overnight and flush with boiling water. You can even get help from professional plumbers via plumbingfremontca.com/clogged-drain for any kind of drain problem.
If this doesn’t seem to work, mixing salt and vinegar can also help corrode grime buildup. Create a solution of equal parts salt and vinegar, let it sit for 20 minutes, then flush with boiling water.
Use a drain snake or wire.
If you’re unclogging a sink, a plumber snake can be very useful. This can also be used in a bathtub or shower. You will start by placing a bucket below the P-trap. Loosen the nuts around the P-trap on either side of the “U” shape.
You should be able to pull it off at this point to see where the clog might be. If the clog is not in the P-trap, you can use the drain snake.
Thread the snake through the pipe towards the wall until you feel any snags. There’s a crank on the drain snake which you will turn to loosen the build-up, and then pull the snake out to remove the clog.
A bent wire hanger can also do the trick in place of a drain snake, but you won’t have the benefit of a coil around the wire for extra grip or the crank to further loosen it.