In a nutshell ..............

Handicapping factors can be broken down into the following areas:

The Fundamentals: Speed, Class, Pace, Form

Secondary Factors: Distance, Trips, Trainer/Jockey, Track Surface, Pedigree, Weight, gear changes, Age, Sex and very importantly running style [leader. on-pacer, mid-pacer or backmarker] and which barriers suit for the distance and track.

A few initial basics I mostly want:
3 to 5yr.olds [not worn out or sick of the whole business], the horse has won in the last year [many a horse hasn't], has won in the conditions, has a reasonable jock and if it won last start has at least a 20% win strike rate and always check for any gear changes [I scrub them off my list if they have ANY gear changes listed] and if a horse has won a race close to the prize money on offer.

A lot of these things can be found out at the AAP site.