Or simply how can I take the best &wisest decisions every time?
We have computers that are 100% efficient so we don’t have demonstrate that kind of mental accuracy. And often, incorrect decisions have led to great discoveries. For example the person who discovered the un-stickable glue on sticky notes was actually trying to produce a glue that would stick to everything. Instead, he found a glue that would stick to nothing and was useful to everyone.
So, 100% efficiency is not a great thing to strive for because there are happy accidents.
Also, taking the long view, a decision that seems great at the time can be disastrous down the line. We have many examples of this: Atomic bombs, malfunctioning nuclear power plants, and pesticides that are toxic to people, to name a few.
The mind is fallible and not perfectible but the Soul is always perfect and always assists in making the right decision. That is because is is your connection to Universal Intelligence. You can train yourself to stay in contact with your Soul, which many wise people have done. Many great works of wisdom can bring you to this path. Find the one that speaks to your heart.