In today's NFL, the proper approach to free agency starts with acknowledging a simple truth: GMs can't win in this game.
Free agency is almost always a bad value proposition. Teams will always look to keep their top homegrown players. So when a player reaches free agency, often it's because his team -- again, the people who know this player the best -- decided his projected production will not match the price of the contract demands. And if the team that knows the player better than anyone else is taking a pass, that clouds your evaluation before it even begins.
That said, players can also be on the market simply because teams are being squeezed by the cap. Sometimes teams can be victims of their own success. They end up with too many good players who all require too much money to keep and they're forced to part ways. Players coming from that circumstance are often better investments -- but they are few and far between. And that scarcity drives their price way, way up.
I took some heat for not spending big in free agency on other people's players, but too often I believed I wouldn't get a good return on the financial investment. So, despite the criticism, I took a very conservative approach to free agency, abiding by a list of dos and don'ts that helped my teams maintain a high level of success in both the short and long term.
These are my top tips in terms of how to approach free agency.
Note: An additional explanation of the grading methodologies can be found here. You can see them applied to the 2014 free-agent class with Bill Polian's Free-Agent Tracker.