The most serious, life changing, choices are never black and white no-brainers. They require decisions like about what job to take or leave, who and when to marry or divorce, whether to have a baby, and whether to give up material pursuits for spiritual pursuits.

Some argue that any decision or choice you make is life changing. Jean-Paul Sartre says "We are our Choices." What we choose to do sets off a chain reaction that affects our future and the future of others. It is the law of karma - what we do colors our mind and causes effects into the future. Consider the decision to give a dollar to a homeless person. How does it change you? How does it change the homeless person?

Uncertainty
Not only do you have to live with the consequences of your decisions, you have to live with the knowledge that you won't know what the consequences will be until after you make the decision, act on it and it plays itself out.

Everything is subject to change. We live in a complex system in which billions of people with diverse ideas, cultures, levels of education, vast differences in financial stability and basic security, live together in an increasingly shrinking space. Mountains and oceans are no longer barriers to travel and communication. A change in one part of the system ripples through, with more or less impact on other parts of the system. For example, spray insecticide or genetically alter the crop on one field and airborne seeds and bee borne pollen infect other fields, birds eat insects , animals eat the birds, new insects appear, new strains and poisons are needed, poisons enter the water sources and streams, people and other animals drink the water. We learn to distrust nature.

Do We Really Need to Make Decisions
The Third Zen Patriarch, says,
"The Great Way is not difficult for those who have no preferences.
...
If you wish to see the truth, then hold no opinions for, or against, anything."

Without preferences it seems as if there is no need for decisions. The universe will unfold as it will and one simply goes with the flow.

This approach may be fine for a person who has given up attachments and is living the life of a Taoist yogi monk. But, for those who have not yet become fully enlightened and live the lives of householders, with jobs, families and a preference for creature comforts and positive outcomes, it seems a bit impractical. Decision-making is a vital part of our lives. Even deciding not to make a decision is a decision. There is no way out. If you are a human, living in the world you have to make decisions.

How Do We Decide?
How do we choose or make decisions knowing that we are creating our future and knowing that whatever we decide, however we go about deciding it, outcomes will be uncertain?

Foundation Concepts
Start with a basic understanding of how things are: uncertainty is a fact of life, any decision can be changed, you cannot change the past and you cannot change the present moment, you can influence the future, which begins with the next moment, but your influence is limited. 

Make decisions without being attached to their outcome. If they turn out well, fine. If they turn out badly, fine. Just stay calm and carry on. 

Nonattachment is a tough one for many people. It does not imply that we don't care about the outcome, it is simply a recognition that we are less stressed and more likely to be able to carry on most effectively when we are not hung up on how things should have or would have turned out. Accept the way things are, whether they are pleasant, unpleasant or neither. With equanimity comes a calmness that enhances mental clarity and avoids unnecessary stress.

The attitude of being an actor in a play who is immersed in his or her part, and who is at the same time not fully identified with it, makes decision-making easier. It is when you are identified with your role that decisions take on a life and death seriousness. Anxiety over whether the outcome will be satisfactory to you or others is the result. Anxiety clouds the mind and makes for poor decisions. When you are in touch with the part of you that is not effected by the drama unfolding around you, consciously working on yourself, you can transform anxiety into something positive. Anxious feelings become signals that remind you that you have forgotten reality. Instead of freezing in a state of fear, analyze and reflect.

With the foundation concepts in mind, apply analysis, intuition and an attitude of equanimity, to make decision making anxiety free and effective.

Take an analytical approach. Identify your objectives and decision criteria, assess the options and decide. At the same time use your gut feel, the alignment of the stars, or apply whatever other divinitory method you can bring to the deciding. Analysis does not preclude taking a more intuitive approach and taking an intuitive approach does not preclude analysis. The two feed off one another. Analysis enables you to reality-check your intuition and your intuition provides reinforcement for the analysis. One without the other is working with half your brain.

Know Your Objectives  

"Alice came to a fork in the road. 'Which road do I take?' she asked.
'Where do you want to go?' responded the Cheshire Cat.
'I don't know,' Alice answered.
'Then,' said the Cat, 'it doesn't matter." - Carroll, Alice

Why are you making the decision? What outcome do you prefer?

What are the Criteria?

Every decision is based on an assessment of a set of prioritized criteria. The more conscious you are of the criteria, the greater the clarity of your decision-making. If you are deciding about a job, is income more or less important than working conditions, security or the meaningfulness of the work? What are the practical issues and risks? Why will you make the decision in one way vs. another?

What are the Options?

Identify your options. There has to be at least two, doing or not doing. Often there are several and sometimes there are an infinite number of possibilities that combine elements of options into hybrid solutions. When confronted with a large number of options, decision making is difficult. Narrow the options down to a few principle ones and make a major decision among them before going on to making a series of minor decisions about the way the major decision will be acted upon. For example, before you get involved with choosing a paint color decide on the house or apartment you'll be getting. When there are too few options, then the decision making is unnecessarily constrained.

Assess 

Assess each option with respect to the criteria. If you need to justify your decision, take a more mathematical approach involving numerical weighting and scoring of your options. If you are making a major decision, it helps to write down the objectives, criteria and options so you can more easily reflect on them and open them up to others.

Let the Decision Emerge

In Heinlien's Stranger in a Strange Land, the Martians, who lived forever, would "sit" with a decision after they analyzed the situation until they Groked the answer. That could take decades or centuries. Generally, we don't have that long, but there is less of a hurry than you might think. Let the decision emerge. Don't force it. Let your intuition, informed by your analysis bring you to a decision.

At the same time, be aware of any real deadlines or time constraints that you have to consider.

Consciously Decide and Act
Give up the belief that you are actually in control and your decisions will somehow mold the future into just the future you want. Remember the foundation concepts. Remind yourself of them whenever you are experiencing indecision and anxiety.

As with anything you do, make your decision making an object of mindfulness. Step back and objectively observe the process; let it unfold.

Decide and act. Accept that whatever you do will have uncertain consequences. Know that you will have opportunities to make future decisions that can mold the outcome.