Decision Support Methods

When it's time to do an important decision. I'm really afraid of choosing the wrong way. I keep thinking and thinking but I cant reach the decision. I know now, the problem is there are too many elements I cant process all. So, I'll write them down on a paper and use decision support methods like:

Pros and Cons Analysis
Kepner-Tregoe(K-T) Decision Analysis
Analytic Hierarchy Process (AHP)
Multi-Attribute Utility Theory(MAUT)
Cost-Benifit Analysis (CBA)
Custom Tailored Tools