You have seen how BACKING odds work when you are placing a bet with a Bookmaker. Now, all there is to understanding LAY odds, is to reverse the role. You are now the Bookmaker and accepting bets from others. Look at the examples again (Chapter About BACK Odds), but this time put yourself in the Bookmakers seat.
When you look at the layout of the Betting Exchanges later in this manual~ in our case Betfair, you will see two sets of odds one for those wishing to "BACK" A CONTESTANT TO WIN and one for those wishing to "LAY" A CONTESTANT TO LOSE.
You will select the LAY odds if you wish to act as Bookmaker. Put simply, it means other users of Betfair will be placing bets with you, as if you are a Bookmaker. They will be betting on the contestant to WIN, whereas you will be looking for the contestant to LOSE.
When LAYING you will be looking for, or asking for, as LOW ODDS as possible.