The reason laying is hard is that the odds on betfair usually are much higher than the tab.

When you are looking for selection methods for laying you to think about the tab takeout and the betfair takeout.

TAB takes approx 15%. Betfair takes approx 5%.

Using these figures if you can find a method which has a return of less than 80% (-20% LOT) on the TAB you will be close to breaking even on betfair.

A lot of people thinks it is easy to pick the losers but the long shot will get up and will cause you to come back to approx break even.

For instance a random sample using a random horse from over 10,000 races still gave me a return of 83% - 89%( ran through it 5 times ).

Good Luck.