Much has been of the concept of decision fatigue: the more decisions you make, regardless of significance, the harder it will be to make good decisions. The standard solution is to simplify in order to make fewer decisions.
Barack Obama, Steve Jobs, Mark Zuckerberg, and Albert Einstein all have a uniform of sorts for this very reason. By not having to think about what to wear every morning, you can free your mind for more important tasks.
You can both not have to think about what you're going to wear and not have to wear a black turtleneck every day. First of all, you should have an interchangeable wardrobe. Every shirt should be able to be worn with every pair of pants and shoes. Then you can just pull the next shirt and next pants out of the closet in the morning. Finally, you should probably only have enough clothes for two weeks. This will force you to keep things simple.