One thing we often forget when we talk about mental blocks is that some of them are simply mental overload. We don't have the mental bandwidth to figure out an approach to the problem in front of us, as well as everything else in our life screaming for attention.
Fortunately, most of the time, we don't have to reinvent the wheel. People have already come up with ways to break down the most seemingly-onerous tasks into manageable chunks and processes.
Here are just a few examples.
Structured thinking approaches new problems and questions by looking for ways to get the information you need, like Neil deGrasse Tyson's example of a job applicant being able to estimate the height of a building by measuring her own shadow against its shadow. It sounds simple, and it is. But the ancient Greeks accurately calculated the circumference of the Earth by breaking down the problem into simple geometry.
There are very few people who would contend that Warren Buffet is an idiot. His rules for investing are clear-headed, long-term and simple. He invests in what he understands, and he devotes his time to understanding it very well. If you could only make 20 investments in your lifetime, or create 20 products, or make 20 life decisions, you would focus a tremendous amount of thought and effort on making those choices the best they could be. That's the power of focused effort.
Turn Off Stress
There are two kinds of stress, eu-stress, productive stress, and distress. Why let distress stand in your way? Have a process for swatting it when it appears. Whatever time you invest, it will be less than the inevitable extra time it will take to tackle whatever's on your plate while you're stressed (not to mention the obligatory 2x multiplier for procrastination).
Conflict aversion is one of the most common sources of mental overload. It can immediately turn on our fight or flight response and take us right out of creative mode. Having a process for various types of conflict is one of the best ways to avoid that feeling of overload, and the counterproductive impact of that feeling on the conflict itself.
Believe it or not, in almost any given situation, there are dozens or hundreds of ways to think about a problem that don't occur to us because of our own background. Different ways of thinking develop in different professions and walks of life, and sometimes, it makes sense to try to see our problems through the lens of one of those other thought processes.
Sometimes, our brains just need a slight change of perspective to see where our current problems line up with possible solutions.