If your toilet becomes clogged, a plunger can normally be used to dislodge anything stuck in the pipes. Simply push the plunger over the drainage hole and pump it vigorously. Don't flush the toilet during this process or you may cause the basin to overflow.
If your bathtub or sink clogs, you may be able to use a plunger on those pipes, too. You can also purchase a drain cleaning tool from a local hardware store, which will allow you to fish foreign matter out of the drain.