Aurelion Sol vs Yone

Keep Breath of Light (Q) on the same champion: each second triggers a burst of bonus damage and gives you Stardust.

Farm with Singularity (E): every enemy that dies inside, minions included, gives you Stardust, which permanently strengthens all your abilities.

Cast Astral Flight (W) to escape a gank or to chase: during the flight, Breath of Light (Q) has no cooldown and no channel limit.

Cast Falling Star (R) on several enemies: it stuns them, and each champion hit gives you Stardust to upgrade your next cast into The Skies Descend (R).

Get out of his line after two Mortal Steel (Q) hits: the next one makes him dash forward and knocks the enemies hit into the air.

During Soul Unbound (E), avoid taking hits: when he snaps back, part of all the damage he dealt you is repeated.

If you have ground-targeted CC, place it on the body he left behind: when Soul Unbound (E) ends, he has to return there.

Judge his threat by his crit items more than his level: Way of the Hunter (passive) raises his critical strike chance, so each crit item does more for him.

In teamfights, don't line up with your allies in front of him: Fate Sealed (R) hits every enemy in a line and knocks them into the air toward him.