Landing Crescent Strike is critically important, but don't be afraid to miss. The cooldown is short and the mana cost is low.
Consider when to cast Lunar Rush without Moonlight and when to wait for another Crescent Strike.
Use Moonfall and Lunar Rush to stay on targets and activate Moonsilver Blade for extra damage.
Dodge Crescent Strike, or move to safety if you are affected by Moonlight.
Pale Cascade orbs only last a few seconds. Avoid Diana and engage her after the shield dissipates.
Diana can play very aggressively if she uses Lunar Rush without Moonlight, but you can punish her by slowing or stunning her when she has no way to get back into position.