Bid less.
all smartassedness aside this works well. What I do is let auction sniper do all the work. Lately I've been buying PS2 RPG videogames. There are usually 5-10 copies of each game that I am looking for online. I search the "completed" items and order them priced highest to lowest. This gives me an idea of what people have paid for that item and from those figures I decide its worth. I then snipe via bidgroup accordingly.
This doesn't work as well if it's a rarer item that doesn't appear as often on eBay.