Simple, as most things are unless we insist on making them huge, extremely important (as in "it should have been ready yesterday") and complicated (as in "it's so complicated, I would explain it to you but you wouldn't understand it").
If you have a warm, fuzzy feeling after doing something, then you most probably did the right thing. If you feel your stomach turned into an empty pouch, if you wish to turn back the time for only a few minutes... Then you did the wrong thing.
Too bad with this easy-peasy-lemon-squeezy rule for the peace of mind you only figure it out after the event. A posteriori. And there are some of us that didn't yet understand all wisdom lies in the guts. True, knowledge and information live up in the penthouse. But wisdom... that's another story.
One that has to do with the way we connect to ourselves.
I have come to understand over the past few years that the most precious asset I have is my own peace of mind, my own state of ever-curious calmness, my own peace made with myself and the astounding combination I am (the astounding combinations WE ALL ARE).
If I have it, the possibilities that lay in front of me are innumerable. I can basically do anything I want, I can start anything that pleases me and, most important, I can STOP doing whatever brings me a negative balance: it takes out of me more that it gives me.
The only way to figure out if a certain decision will bring you peace of mind or torment-in-rates is to sharpen your intuition. Listen to what your stomach has to say.
Yet we, the hyper-rationalistic victims of left-brain-based education still laugh at intuition. We laugh at dreams. We laugh at signs, flows of energy and horoscopes. Because we can only believe what we can see, not realizing that by saying it so proudly we actually tell the world how little we CAN actually see. Or do.
We laugh because we believe intuition wears wavy, flowery skirts, big bangle earrings, turquoise make-up and cries at romantic movies. We rarely see beyond the skirt and the handkerchiefs. We rarely see it takes... let's call them... guts to act upon whatever you believe in. And they hide *ummm, how to put it* under the skirt :)