So this deck works more as a mid-range than you'd expect Sparkmage to be. And it's super fun.
Let's start with your mulligan. You want to see Poisonous Dagger, Drums of Doom or Silver Bullet in your opening hand. If one of them isn't there, just mull all 3 spells. The only exception to this is Highland Princess. Keep her if you get her. If you do get one of those 3 cards in your opening hand mull anything you see fit, but most of the time I don't bother.
The Game Plan: Get to 6 stable mana as quick as you can. Stable meaning 6 mana every turn. Weather that's 5 sites and the core, or just 6 sites. Use the bonus quick mana from Towers and Ghost Town to drop minions and/or artifacts a turn early, but try not to use your magic unless necessary to remove something truly problematic. Once you have your stable 6 mana online, you're gonna go on the offensive. Drums or Dagger should already be carried by Sparkmage, so your gonna use movement magic to put him in advantageous spots and use his tap ability to start clearing out enemy minions. Daperylls, Ranatus and Hippogriffs will do most of your damage, but if you get into a good spot where the enemy minions are well controlled, start dropping your damage spells on your opponent as well.
Highland Princess target: Kythera Mechanism. Every. Single. Time. Not only is it important to control what targets your Sparkmage hits, but your Thunderstorm and 13 Treasures of Britain as well.
2 cards that aren't amazing, but are really good in this deck: Recurring Specter and the new Hexham Haunts. Both of these can be CAST from your cemetery. Meaning that even if you have no cards in hand to play, you can cast them and get the threshold needed to use Sparkmage's second ability.
Site notes:
Altar of Malachai: Try to cast a Recurring Spector here. If not that, an Apprentice Wizard.
Battlefield: If you draw into one of these, try not to use it unless you can get a Poisonous Dagger back from your cemetery. If it's gonna be your 6th mana, so be it, but if your opponent is in air and/or earth, I'd save it.
Trade Encampment: This is here so you cant trade one of your other 1 mana artifacts for Amulet of Niniane if needed from your collection.
Mountain Peaks: Seems like overkill in a mono air deck, but we need to get to 3 threshold, and we have a lot of non-threshold sites. So we like these.
The Collection:
Poisonous Dagger- in here as the primary target for Silver Bullet.
Bull Whip- if you already have a Dagger out and want some more minion control.
Amulet of Niniane- Used with the Trade Encampment if you come across a magic heavy deck like Archimago or Animist.
Disenchant- Situational get rid of stuff.
Tactical Move- Just extra movement for your board if needed.
Murder of Crows- for any token strategy. Also can be cast for a second time from the cemetery, and we like that.
River of Blood- Yeah, not ideal since you have 5 vampires in the deck, but if they're gonna Font of Life, it's worth it.
Haystack- If you so much as smell a Common Sense coming, just pop this out.