Back or Lay
In the first time when you using a betting exchange, you can "BACK" or "LAY" make a selection.If you BACK a selection (be it an individual, a team, horse, dog or other), you are betting that it will win. This is just like betting with conventional bookies website. don't worry about win or lose first.
When you "LAY" it, you are betting against it winning. For example, if you're betting in a market on which team is going to win the Premiership and you lay Man Utd, you offer odds to other punters who wish to back Man United. If Man United don't win, then you pick up the backer's stake. If Man United win, then you pay out. This is what bookmakers traditionally do.
You never know who you are betting against, your privacy and the confidentiality of your bets is maintained by the exchanges secure site.
Choose odds Market
You must to be understand and choose odds to play in every market you decide.There is always a choice of what odds to accept. If you want better odds than are currently available, you can place an order for a better price, but be realistic because there has to be somebody prepared to lay the bet at those odds, and vice versa.Take a look at the odds before a game and you will see them change as visitors back and lay their bets. The odds often improve nearer to the off, as there are more people in the market.
Earn Commission
Commission is a benefit you get from bookies website when you have making a win lose calculate, they will pay you some from your bet place.You do not pay tax but commission is paid on your net winnings on each market. This is particularly beneficial if you have multiple bets on a single market such as the Premiership Winner market. Some of your bets may win, some may lose, however you only pay commission on your NET winnings. If your bets in a particular market amount to a net loss, you do not pay commission.
Your Commission rate is set according to how much you use an exchange.
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source: Google