Jungling:

• Imbue health-sustain meanwhile jungling;
• Gemcraft mana-sustain meanwhile jungling;
• Attack Speed has synergy with Imbue and Gemcraft.

Ganking:

• Shatter deals AoE damage+debuff;
• Shatter and Radiance give AoE buff to teammates;
• Dazzle is a stun to initiate.

A good start is to see the skillset of a champion and try to understand the possible synergies between abilities and then to decide what to do to improve them.

1) It's the case of Taric, Gemcraft and Imbue have a synergy with Attack Speed, so one goal is choose masteries and items with Attack Speed.

2) Gemcraft synergies well also with Attack Damage, and having attack damage and mana-sustain for a jungler is good, eventually at the beginning. Attack damage can be added with masteries and runes.

3) Like other ap-champions, there are 2 weakness: first one, magic resist doesn't scale on level (but with the new patch, YES!); second one, meanwhile the skills are on cooldown, the champion is useless and easily target-able cause his nature of melee.
I'll try to cover these weaknesses with runes and items, it's a problem of survivability.

Goals:

• Attack Speed, covered by runes, masteries and items;
• Attack Damage, mainly covered by runes and masteries;
• Survivability, itemization.

With runes, it's possible to improve the jungling clear and survivability.

Jungling Survivability:

• Greater Seal of Armor*9: unmovable runes, they give enough armor to safely clear the jungle.

Jungling Clear:

• Greater Mark of Attack Speed*9: Attack Speed with marks, help a lot to clear and sustain the mana;
• Greater Quintessence of Attack Damage*3: chosen instead of Greater Quintessence of Ability Power because they synergy well with Gemcraft and with the clearing. Starting from wraiths, these quintessence kill each minion with a hit less.

General Survivability:

• Greater Glyph of Scaling Magic Resist*9: Taric's magic resist, NOW, scale on level, but these runes are still viable.
• Greater Glyph of Magic Resist*9: regular flat mr runes for any jungler, now Taric can use them.
• Greater Glyph of Ability Power*9: help in damage output for a faster clear and good early burst damage with spells.

Taric needs mainly attack damage and attack speed, good mobility like any jungler. The trees that can add these features are the offense and utility one.

First, in defense tree there's an unmovable point to set:

• Summoner's Resolve , 1 point: +10 gold smiting is duty and law for a support jungler;

20 points to spend in offense tree:

• Brute Force , 3 points: synergy with Gemcraft and jungling;
• Butcher , 2 points: faster clearing;
• Alacrity , 4 points: core points cause of Attack Speed;
• Sunder , 3 points: needs to clear faster, if you have the right runes, it permits to take different routes and kill minions with fewer hits;
• the 8 points left are free, but in order to get Sunder it needs to spend them in offense tree; i use them for Deadliness Vampirism and Weapon Expertise , but early game aren't that important, maybe Sorcery is better.

The 9 points left are going to be set in the utility tree:

• Summoner's Insight , 1 point: having reduction in Flash is always good;
• Improved Recall , 1 point: I like to spend 1 point to recall faster and save time;
• Swiftness , 4 points: core points, easier chase.
• Good Hands or Expanded Mind , 2 points: are both pretty viable.
• Runic Affinity , 1 point: must for a support jungler.

Starting items, and early items are chosen to have a faster clear and survivability.

1) Starting items:

• Cloth Armor + 5 Health Potion: classic start, with this set-up it's possible to start from wraiths->wolves->blue;

After some recall, you need to have this set-up:

• Cloth Armor: from the start;
• Kindlegem: health and cooldown.
• Boots, or early Ninja Tabi or early Mobility Boots;
• Dagger: Taric's jungle-sustain;

2) At this point it's possible to upgrade the boots.
Viable options:

1. Boot's of mobility: lately I'm using these boots and, believe me, they are really great, they make insanely everything: movespeed, chases, ganks. Maybe they'll become core-item really soon.
2. Mercury's Treads: best (!!!no more sure about that!!!) choice for magic resist and tenacity;
3. Zeal: my choice, yes, you can skip and upgrade later the boots for it, it's nearly a core item for Taric because synergy well with everything, more Attack Speed, more Damage after Shatter Radiance and mobility.

3) Time for core items:

• Mercury's Treads: if delayed their upgrade;
• Zeke's Herald: time to finish Zeke's Herald, it's the best item on Taric, attack speed and life steal for teammates + cooldown;
• Aegis of the Legion: cheap, another aura item for Taric.

Closing the core items, Taric'll have good defense between armor and magic resist, with about 2300 hp.

4) From now on it's possible to focus on defense or health with end game items:

1. Abyssal Mask: another nearly core items, makes Taric's aoe damage impressive.
2. Randuin's Omen: not that cheap but gives health and brings Taric's armor over 200.
3. Trinity Force: after buying Zeal, this item can be an end-game item.

5) Remember to take Elixir of Agility, Elixir of Brilliance, Elixir of Fortitude, Oracle's Elixir.

Take Radiance every time is possible, greatbuff for Taric and teammates, also good Aoe damage.

Maximize first Shatter, taken it at level 1 to have more armor, more damage in jungling, and more debuff armor. Remember to use that wisely during the fight.

The second skill to maximize is Dazzle. Take it at level 3 for an early gank or at level 4. It has a fixed mana-cost, improved damage and cool-down at high ranks, good initiator skill.

Why Imbue at last?
Because his mana-cost is high at rank 5, and you just need that to sustain your jungle at the beginning.

One summoner's spell is a must:
Smite: clear faster, more gold, ability to steal important dragon or baron.

The second spell can be:
Flash: really good in defense to back over a wall, in attack to follow someone over a wall, to make some tricks like Flash + Dazzle / Shatter / Radiance combo;
Ghost: viable spell to improve speed and chasing better, but remember to put a point in the mastery offense tree Summoner's Wrath .

Taric isn't a high tier jungler but i think that his skillset is average to jungle.
His passive Gemcraft seems to be done properly for jungling and also his cool-down reduction on Imbue.
Shatter makes him tanky, meanwhile Dazzle is good to gank/initiate.