Next time you are near a pool table take note of the large buttons on the top of the rails, these assist a pool player in escaping from snookers (known as the 'Diamond System'. I have divided each rail on my full size snooker table & put 3 stickers on each, With practise when aiming anywhere on the table to one of these spots, you must use running side, you will see the cue ball go from one spot on a cushion to another and to another.
There is a mathematical way of determining the out as each spot on the rail has a value. I suggest you find a pool book which will show the 'Diamond System' in more detail. Though I probably don't use the system to it's full potential it certainly allows me to understand how to play out of snookers off more than one cushion.