That is done by placing an earlier, higher bid.
eBay only displays enough of the highest bidder's total bid amount to be able to take the lead by up to one bid increment above the previous high bidder, if any.
Because of this, many veteran bidders suggest deciding how much an item is worth to you in advance, taking into consideration any shipping or taxes, and then bidding the appropriate amount once, as late in the auction as you are comfortably able to do reliably. If the amount is a round number, adding a few odd cents will decrease the chance of a tie bid, which would go to the earlier bidder.
If you are able to successfully bid your maximum amount in this manner, the only way you can lose is if someone else is willing to bid higher than your maximum bid and actually does so before the auction ends, or if someone has already bid the same amount, earlier.
