Pick off the runners.

Depends, if you're carry is gonna get blown up then sit back with him. Their bruiser/assassin will dive in and this is when you get your first kill. After that use rappel to dive onto one of their carries and kill them both, with 3 kills you then finish off the tank/supports for the penta kill. If you're carry is safe then skip step 1 and kill the bruiser assassin last or mid fight.

You try to nail someone important with your stun then your team should initiate.

After initiating, you whittle down the tanky champions with your %health damage and rappel to someone if they try to run and finish them off.

its fill, you can initiate, you can hang back and defend and poke down runners, you can swap back andforth.

Its not all or nothing.