To engage from a long range W to an allied unit then Q and Flash mid animation. Once you confirm Q will land use R.
Another way to proc your stun is to Q the enemy then instantly W to an allied unit near your target. AA three times to proc your passive.
To quickly engage on a target R Q and W to an allied unit as fast as you can then AA three times.
For a quick way to save your ally Flash and instantly W to them, then Q as soon as you land. Follow up with AA R and then AA twice to proc your passive.
To save an ally in danger W to an ally then E Q R instantly
A common way to stun your opponent is to W to an allied unit then AA Q and AA twice more for your passive to proc.
Your standard level 6 combo is to Q AA then instantly R. AA twice more to proc your passive.