Introduction: Taric has amazing AP ratios for his stun (1:1) and heal (1.1:1) and can become a great support/damage character in mid to late game. Shatter can deal decent damage since it has a high base damage and you shouldn't be afraid to use Shatter. His cooldowns are long and he needs to be played patiently; greed is not rewarded while playing Taric. The blue buff is a key aspect of playing him since it reduces his cooldowns by a considerable amount as well as gives him increased mana regen to sustain his ultimate.
Masteries: I build him as an AP off-tank, which results in bigger heals and more damage. So for the masteries I chose to go 9/21/0 for a good solid defense and magic penetration.
Skills: First thing I get is stun then heal then shatter. Afterwards I prioritize as such: Radiance>Shatter>Imbue>Dazzle. Level one Imbue should be sufficient enough for laning phases. If you find yourself needing a higher level Imbue then you aren't playing Taric right.
Runes: Pretty typical AP stuff.
Items: I start off by prioritizing cheap defense items such as Chalice and Ninja Tabi's. If you start with Meki's first that means on your first trip back you would like to have 1350 gold to buy both the Chalice and Ninja Tabi. I then think more offensively and shoot for the Abyssal Sceptor. This item is also great for team fights and helps your AP allies greatly. From there I try to get a glacial shroud for cooldown since Taric has fairly long cooldowns. The Frozen Heart is a bit expensive and I like to split up with an item in between, so I choose the Arc Angel. The Arc Angel gives you more mana regen, more mana, and AP; all things Taric loves. After completing that I finally get the Frozen Heart. The 6th item is not an item I usually get since this item build is reasonably expensive for an off-tank. It could be a Zhonya's if you are feeling you are tanky enough or a Guardian Angel if you feel you are not tanky enough.
Strategy: Play like a Sion. Sit in a bush and then stun at the best moment. Go out and shatter then maybe land one hit. Go back into the bush and repeat until they go back or die.
Early Game: Try and maintain bush control if you can because Taric does well in a bush since he has a ranged stun. Employ the above strategy for whittling down your enemies or killing them. I find the level that Taric is most deadly is at level 5; when you have level 3 Shatter. This is usually around the time I try to aim for a kill. If a kill doesn't happen at level 5 then if they are low health by their turret you can dive them for the kill or wait till level 6 for a safer dive. At level 6 you can pop your ultimate and take a bit more turret shots.
Mid Game: This is around the time Abyssal Sceptor has just finished and teams are starting to group up. The tankiness hasn't really kicked in yet, but you can take a good bit of damage thanks to your heals. You should begin every team fight by stunning their squishy, Shattering him, turning ultimate on and continually hammering him into the ground. Heal allies when necessary. The Glacial Shroud should also be on the way and when you obtain it you are pretty tanky and deadly because of the cooldown.