Mirana is a very versatile and mobile semi-carry, with decent burst damage and the ability to fit into almost any line-up and lane anywhere.
Skills
Grab an early point in Leap so that you can safely escape ganks and Sacred Arrow so that you have a potential stun in your arsenal.
Max Starfall first, then Sacred Arrow to complete your burst potential, and finally Leap.
Be sure to get your ultimate, Moonlight Shadow, whenever you can (so levels 6, 11 and 16). It's a great initiation skill (it can function like a Smoke of Deceit) and an escape ability for your entire team.
Items
Mirana is a semi-carry; in order to be relevant past the mid-game you'll need at least your core.
Starting items: Tangos, Healing Salve, three Branches & one Slippers of Agility.
Core items: Phase Boots or Power Treads. Magic Wand. Ring of Aquila or Bottle. Yasha into Manta Style.
Situational pick-ups: Black King Bar, Orchid Malevolence, Mjollnir, Diffusal.
Good luxury items: Assault Cuirass, Butterfly, Monkey King Bar, Daedalus, Desolator.
