Metrics for stock evaluation

[amoeba]

An investment newbie here.

After reading a few books, I understand the general idea of diversification etc. I also understand that when buying specific securities (individual stocks) instead of index funds, sufficient research is required.

Thus, I would like to ask what metrics is most useful when researching individual securities.

Just as an example, when I'm looking to purchase a growth stock, how much weight should I put in to say its PEG ratio?

Also, when evaluating a security, if you were to list the metrics from most important to least important, what would they be?