Toilets
If your toilet won't flush properly, you can typically resolve a clog using a plunger. Do not flush a toilet that is clogged, as this could cause the toilet to overflow.
Sinks/Shower
If your sink or shower won't drain properly, there may be hair or other debris in the drain. You can attempt to clean the drain using a cleaning tool, but please do not use drain cleaning chemicals, as these could damage your plumbing system.