What is the order of actions the driver needs to take before slowing down?

Give a hand signal to the driver behind, glance at the mirror to see his response and slow down.

Turn your head backwards, step on the brake pedal to slow down and finally take a quick look at the mirrors.

Step firmly on the brake pedal, to inform the driver behind you began to slow down.

Glance at the mirrors, ease off the accelerator pedal and use the brakes or gears.