Use a racing website such as https://www.racingpost.com/
Go through each race card for the day and follow the steps:
STEP 1
Note all NON-HANDICAP races both for Flat racing and Jumps including the ‘All Weather’ courses. With between 5 and 12 runners inclusive.
Exclude amateur jockeys or apprentices claiming the full 7 lbs
STEP 2
Note the price quoted for the favourite and the 2nd favourite in the betting forecast.
STEP 3
There must be LESS than 4 points clear difference between the two, eg:-
FAV Evens – 2nd FAV 4/1 or more (2.0 to 5.0)
FAV 1/2 – 2nd FAV 3/1 or more (1.5 to 4.0)
And so on.
STEP 4
Bet on both the favourite and 2nd favourite.
Then bet accordingly, using dutching or straight stakes according to your own preference or waging strategy.