Cause and effect essays focus on one major event and elaborate on the reasons why the event happened (causes), and the results of it (effects). Some helpful techniques include picking a topic with easily recognizable causes and effects, narrowing it down and adopting a chronological approach.
Selecting a topic is one of the most important steps in any essay writing. For cause and effect essays, you should focus on an event or a trend that has relatively obvious (and easily distinguishable) causes and effects. Some key questions to keep in mind are: "Why did this particular event happen?" and "What happened because of this?" Write down the answer to those questions in two separate columns, as they are the guiding principles organizing the entire essay.
Oftentimes, an event has multiple causes and multiple effects. In that case, you have more than one item in each of the two columns answering the guiding questions. The next step involves narrowing down the topic; to do so, focus only on one or two of the most important causes, and write down some notes explaining your choice. Do the same thing for the effects, keeping in mind your goal is not to explain in detail every single cause and effect connected to a certain event.
Lastly, since causes necessarily come before effects, it may be a good idea to structure the essay in chronological order. Elaborate on the situation leading up to a certain event first (the causes), and only in a second time draw the connection to the situation that resulted from that event. You can refer back to the columns to keep track of your progress.