When you are actually out there, be detached from outcomes.Well, while in sports it might fit the needs I would take care of applying that rule to the rest of life.
“I never looked at the consequences of missing a big shot . . . when you think about the consequences you always think of a negative result.”
It is good looking at the consequences because all the actions you perform will have their consequences and knowing the consequences before would often lead to other decisions.
Thinking of (possible) consequences does include thinking of negative results. If you think of a failure in general as an opportunity to learn then failure is never considered in a negative way and positive experiences will be the "only" harvesting the fruits of earlier improvements.
When thinking of negative results produces negative feelings and fears then you should separate first the facts then think of the risks. In the next step analyze your fears coming along with thinking of the risks. Last but not least take your decisions when you can have a detached view so that you do not feel so emotionally involved.