In & out

Inhale when your arms come in, exhale as your arms move out.
Inhale as the arms lift, exhale as they lower.

Inhale as you lift to kick...

This may seem odd until you consider the difference between a hand or leg strike. With the hands or body, you shift from one leg to another as you strike. Yet, with a kick the weight is in one leg only - the supporting one. As you lift the body and kick, you inhale. If you exhaled as the leg rises, your balance would follow your breath.

We only exhale for kicks that are inclined downward, and are using gravity and weight.