1) Extended discussion of simple actions—If someone is leaving the house, this should be accomplished within a sentence or two. The only reason to go into detail about a character putting on their shoes etc. is if those points are vital to the plot. Readers have imaginations. You don’t need to tell them every little step in opening doors etc.
2) Glossed over actions—At the other end of the scale is when major events take place but the author glosses over them in barely a sentence. If you’ve been building towards a confrontation, but then only say that the character fought the gang and won, it is going to be something of an anticlimax for the reader. Describe the fight. Tell us how they did it.
3) Your favourite things—Let’s say you love Jane Austen, so you imbue your character with the same trait. Be careful that, in your enthusiasm, you don’t go on to give your character lengthy monologues on the topic that have no bearing on the plot.
In general, when you read through your story, check where your principal focus lies. Are you highlighting unimportant characters, places, or events—ones that have little relevance to the plot? If so, those sections probably need some trimming. The reverse is true if you find you have glossed over key figures or incidences. Readers need to know more about something only if it advances the plot or adds to character development. Otherwise, you risk losing their attention while your character waffles on about why Pride and Prejudice is superior to Sense and Sensibility.