So pretty much either bid immidiately after maintenance or during the night. And if you're bitting against more than one player, then drop. And never spend more than 3 tokens on a player. Well, crap. No, I'm only level 3 right now, but at the beginning of the season, people were bidding like crazy. :S Here are some screenshots:

Current Squad Click image for larger version. 

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Auction House w/ current bids $ cash Click image for larger version. 

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