Perhaps one of the best ways to easily catch errors in your tree is to look at the dates of vital events for the people involved. Do they make sense? Is the timeline plausible?
Genealogists should know, as they say, where babies come from. Aside from modern interventions, parents have to in the same place roughly nine months before the birth. They also have to be alive at that same time.
Triple check before you add someone to your tree and don’t just take someone else’s online tree as gospel.
Sometimes a simple dose of “genealogy commonsense bleach” does an excellent job of cleaning. There are more advanced tools that can be used to “clean your tree,” but “genealogy commonsense bleach” will remove the majority of the grime on your tree.