I'm reluctant to use the 'o' word in this forum because it will start Rick foaming at the mouth but you have 2 very [insert that word] points on the ball useful for visualising the quarters.
The top of the ball and the extreme edge of the ball (sorry Duckie). Splitting the distance between the 2 points should be easy or become easy with practice.
I notice there is an Aramith training ball.
Not sure, but position '4' looks like the quarter.
I still wonder if practicing with a marked ball like this and then playing with a normal set is going to really help.