Winning or losing an auction is purely a matter of bidding the higher price. Sniping is nothing more than delayed order placement. Because the order has not been sent to eBay yet, you can change your bid up or down, something you are unable to do on eBay, and no one can see it.
Bid your max once, very late in the auction. Delayed bidding is like when you are sending email, you can send it now, or you can schedule it to be sent out later. Sniping is having your bid sent to eBay later, nothing more. Bidding early in an auction simply telegraphs your intent and attracts others to bid against you. By bidding late you do not leave enough time for anyone to react to your bid before the finish.
The sweet spot is to place your order, far enough before the end, where your snipe cannot be reported in time for anyone to react to your bid. As long as you have the maximum accepted bid, it does not matter when you place your bid. To win, your bid has to be higher than the current auction price by a full increment, and it must beat the first losers highest bid by one cent, and it must be first.
eBay always uses a proxy bidding system, in which you specify your maximum bid value. It is very rare that you will actually have to pay your proxy bids highest price. You will usually either win the item for considerably less money than you planed, or else will lose the auction to a higher bidder.
If a reserve price exists on an eBay auction, always ask the seller what the reserve is. If the seller does not tell you, do not bid. Decide what the absolute maximum is that you are willing to pay, and bid it, ONCE! It doesn’t particularly matter whether your bid is three minutes, or five seconds before the auction closes.
Since tie bids are possible and the earliest bidder wins, it usually pays to bid odd penny amounts on any auction. Further, many items will have buyer resistance thresholds. Prices above which others are reluctant to go. Typical "ain’t gonna go there" thresholds are $50, $100, and $150. Thus, a bid of $102.34 is much more likely to win than one of $97.26.
Taking one shot, making one bid, embodies the snipers tactics and philosophy, of efficiency and stealth. The more interest that you show in an item, the greater the chances of someone thwarting your plans. Your first and only shot, should be your last. Successful snipers take their time in analyzing and sniping individual items in a methodical fashion with a relatively low risk of putting the price up on themselves. You should know the value of the item, and bid a bit more.
eBay has all sorts of powerful search features that let you find price histories and interest levels. Be sure to use "search titles and descriptions" rather than titles only. Remember that only "completed items" represent the final prices. Auctions in progress will usually have much lower than final bids.
You do not want to put the price up on myself. It is the unexpected aspect of sniper fire that gives it power. Snipers are trained in stalking, observation, camouflage, and concealment, as well as shooting. Give as little information about your interest as possible to the second highest bidder to keep them bidding low. Sniping makes use of their inability to strike back. If you are right about the value, are patient, bid a bit more, then you will win. If you are outbid because the other bidder was willing to pay more. It does not matter in the least when they bid!
It is like when you are dicing on the highway. You know the top speed that your car will go, but you only need to stay ahead of your pursuer at the finish to win. Similarly you know the maximum that you will pay, but you only need to stay ahead of the second highest bidder at the end. Do not do anything that will make that car, that bidder go higher.
Just as it is a sniper technique to use two teams approaching simultaneously from different directions, placing a back up bid from a different server eliminates your chances of missing your bid because of network glitches or computer malfunctions.
My winning technique is to look at things that I want (Coup d'oeil), until I have made up my mind the most that I will pay! Then I place my delayed offer and forget about it until I get an alert. I need the first loser to bid the lowest price they think can win, without thinking of outbidding me. If there progress is smooth and good, they can be easily lead into an ambush.
With this strategy, there are only two possible outcomes: You will either be overjoyed at winning, or laughing yourself silly over someone paying too much for the item. This strategy is also utterly and totally immune to shilling, sniping, and other price building or item grabbing ploys. Your defense against being sniped, is to bid your max once, close to the end of the auction.
There are tools on the web that are free and easy to use. You just log into your eBay account through the online interface, and schedule your delayed bids.