It is fact that the best jockeys in each state are usually on the best credentialled horses each saturday. With this in mind I will always look at the best two jocks in Sydney and Melb. (Usually those in form)
ie Melb, Prebble and Oliver
Syd, York Beadman.
Look at all their rides take their best three rides based on win percentage and then take all up win bets. I've had a couple of good wins for little outlay..