It’s as simple as telling eBay how much you’d be willing to pay for an item and then finding out whether anyone else is willing to pay more than you. If you’ve made the highest bid, you win the auction and you have to buy the item.
It’s important to remember that it doesn’t cost you anything to bid. You only have to pay if you winand even then, you don’t have to pay any fees to eBay. (All eBay fees are charged to the seller.) You’ll have to pay the seller the amount of your winning bid, plus any necessary shipping and handling costs to get the item to you.
It’s important that you know all about the item you want to buy before you place your bid.