A toilet is a plumbing fixture that disposes human waste. It is composed mostly of a seat and tubes meant to take the waste to the septic tank. Modern toilets come with a flushing system. The flush uses a volume of water to wash waste down the tube into the septic system. Solid waste, which cannot be flushed, can get stuck in the pipes of the toilet. This can cause a clog in the toilet.
Find out what is clogging the toilet by asking individuals who have recently used the toilet. They could have dropped something in the bowl or could have tried to flush something which cannot fit in the pipes.
Place a few old towels or large pieces of cloth on the floor that surrounds the toilet. This will absorb any water that splashes on to the floor. You can also use old newspapers.
Scoop the standing water in the toilet bowl. Place the water in a bucket. Do not place the water in the sink. Leave enough water for the plunger to work.
Take your plunger and insert it into the toilet bowl. The rubber cup or globe of the plunger should be fully seated on the opening of the drain. The globe or cup should be covered with water. Avoid using a cheap plunger which can break while it is being used.
Push the plunger down firmly then release the suction by lifting the handle lightly. Repeat this process around 15 times. This will increase the pressure on the clog and eventually remove it from being stuck on the pipes.
When you think that the clog has been cleared, flush the toilet. As a precautionary step, take off the lid of the toilet tank. Raise the ball inside the tank. This will prepare you in case something goes wrong in the water flow.
If this process does not remove the clog, squirt dish soap in the bowl. Let it sit for a few minutes and resume plunging. You can also try using chemicals which can dissolve or melt clogs.
In case this still does not work, uninstall the entire toilet and manually remove the clog or contact a professional plumber.