[header] How to do a flip turn (freestyle ) [title] Start your turn when you see the black t on the pool floor. [step] There is a black line at the bottom of your pool lane. The perpendicular line lets you know that the wall is two feet away. 
You can use the black t to let yourself know it's time to start executing your turn. [substeps] This can be hard to judge because it all depends on the length of your legs.