So, what is the best way to approach complex decisions? We recommend you do these three things:
1. Take in all information. Obviously, before you can make a decision, you need to have the information. We should use our conscious mind to gather and encode all the necessary facts pertaining to a decision. Usually, some options can already be discarded in this stage — options that clearly violate a "decision rule" for instance "this apartment costs twice as much as what I can afford".
2. Sleep on it. Now that you have all the necessary information, you need to process it. Because your conscious attention is limited, you should enlist the help of your unconscious. Conscious processes often disturb unconscious processes, so you need to distract your conscious mind.
3. Check the facts. Your unconscious can process large amounts of information, but it is not as precise as conscious thought. There is no amount of distraction that will help you answer an arithmetic question. Therefore, after you have made a choice unconsciously, you should check the facts of your decision consciously. Does your decision do any (serious) damage? Attributes are often interdependent - the value of one attribute influences the value of another: Do all the attributes of the choice, taken together, violate a decision rule?
Obviously, literally going to sleep isn't always an option in the middle of the workday, but you can achieve a similar effect by going running, listening to music, or doing any other task that distracts you from the decision. After a period of distraction, one option usually feels better than the other(s). After you've gone through the three steps above, that's the option you should choose.
So while the thorniest of problems naturally feel like the ones you should burn the midnight oil on until you've reached a decision, the science suggests a different approach — one that produces better decisions and better rested decision makers.