In Thursday's New York Times, Christopher Liss discussed the four ways to make a profit off of your fantasy roster. The piece was very good, and I agree with Liss that to win you must turn a profit in at least one of those ways. In extremely competitive leagues, you probably need to turn a profit in two or three of these areas.
Before you get to this point though, you need to establish a baseline of what you think the players available in your auction are going to be worth. Players like Jason Heyward (who Liss puts in category #1) and Chase Utley (who Liss puts in category #4) will deserve individualized attention and extra consideration as far as your bids are concerned. At the beginning of the process, though, what you want to do is come up with a price every player that you believe is worth bidding on in your auction.
To borrow Liss's terminology, my first rule of thumb is to Be Agnostic. While you do want to stand out from the crowd on a few players, what you don't want to do is pay $50 for Joey Votto because you think he's going to be the MVP or $23 for Rafael Furcal because he already has two stolen bases and you're certain he's going to steal 50. In your first pricing pass, you should try to be as dispassionate as possible with your bids. Make those tweaks based on preferences later.
With the exception of rookies or players coming off of significant injuries, The Past Is Prologue. You want to start out with a realistic baseline based on what a player has earned the last 2-3 years. The temptation is to pay Mark Teixeira $30 or more because he's a big name and he's hit 39 HR two of the last three years. However, the earnings column for Tex the last three years has been $24, $25, and $28 and first base is a stacked position in the A.L. this year. No need to go past $26-27. This is the best way to stand out from the crowd...make sure you don't chase a result that is next to impossible due to past performance.
After you've gone through this exercise, make sure It All Adds Up. Your bid totals should equal the amount of money there is to spend at your auction. It's OK to be a few bucks off on the whole, but if your bids are under or over by a good amount ($50 or more) you're going to run into problems. There is no surer way to wreck your season than to miscalculate your overall bids.
Once your bids add up, now it's time to Tweak, Tweak, Tweak. I do this from the time I finish my initial pass of bids (in late January, in preparation for the CBS auctions) to a couple of days before I sit down for my home league auctions in late March/early April. Some of the tweaks I make are due to changes in roles or situations, but often the changes are due to the price points in the CBS, LABR and Tout Wars expert auctions. If I have a price that's $4 or more higher or lower than the price in one of these expert leagues, it often means that a reality check is in order and I probably should adjust my bid. This isn't always the outcome - just because the experts put an average salary of $29 on Brett Lawrie doesn't mean that I should - but more often than not these auctions are great reality checks for my own work.
The last stage for me is usually where I try to incorporate my Gut Feel into the process. If you're new to auctions, I recommend being as much of an Agnostic as you possibly can the first time or two around. It's easy to think that you're playing a slight hunch when in reality you're putting your bid way too high or way too low. But once you've been through a few auctions, you can start moving your bids up or down a buck or two based on who you want or don't want. In keeper leagues, you should also do this based on positional or categorical need. Again, be careful not to overpay for a position or category to the point where it takes you out of the running.
When all of this is done, I typically have a list of bids I'm supremely confident in using and ready to roll. This is the most important part of the process. Whether you're a genius, agnostic, lucky, or a gambler, you had better have a plan to win, particularly if you play in very competitive leagues like I do.