Hello, I'm Seiketi. I'm a Gold 5, Skarner main. And well, i'll let my stats tell the story.

I play Skarner a lot, I even stream if, feel free to drop by and check it out.
Twitch

Anyway, clearly you are here cause you want some advise on how to play Skarner. Atleast that is my first guess. My second guess is, you are wondering "Why should I play Skarner?". I hope to awnser both of those questions in this guide today.

I've included two jungle pages that I prefer to use for the jungle, and a recommendation on a third for support, if you choose to use him in that role. (I wouldn't, but it's possible! I've done it!)

Lets go over Page 1:
Resolve, cause you're Skarner, you tend to be you team's front line, or engage. You need health. Aftershock in it's current state goes very well with how you build Skarner, and the secondary keys help him even more. Increased Armor/Magic Resist, Tenacity and Health are all great stats on Skarner.

Now about the secondary tree, Inspiration. The reason I choose this tree is mainly cause of one second key: Future's Market.
Skarner has a VERY expensive build, mainly due to trinity force being almost always a must buy for him. This allows you to go into debt a small bit, which helps you get to that power spike a little sooner.
Approach Velocity is nice for that little burst of movement speed also.

Page 2: I feel this page is more useful, if you just feel like you have a good chance of snowballing, being the other team has a immobile mid or ADC, or maybe just not the best support. Something that you can take advantage of. The only difference in between these two pages is the secondaries, this one being of: Domination.

Cheap Shot: Cause Everytime you E, you proc this for free damage.
Relentless Hunter: More Movement Speed on Skarner per kill/assist. Helps you get around faster, which means more or better ganks/escapes.

Skarner:
Your Blue, Gromp, Wolves. (Try and secure atleast your netural spire, if not the one in the enemy jungle. Be careful, they are useally contested. Do not goto the enemy one without someone nearby.)

Look for Gankable Lane, Get Skuttle, then head to that lane. (Unless you need to get there sooner, then go straight there.)

If no lanes are prime for a gank, finish you're jungle, back, and look for a gank then.

Another note: Skarner has AMAZING clear after his first full clear, and it's easy for him to go counter jungle the enemy jungle, his W helps him get around faster, but be careful it uses a lot of mana. I always check the enemy raptors, whenever I'm nearby them.

Skarner works best when there are other CCs that can either setup, or follow up on his CC, also, if there is another front line to split up the damage. But you're goal is to get whoever the largest threat is, either out of the fight by killing them, or peeling them away from your team, depending on who it is. (General Rule is Squishy, Drag them to your team. Everybody eles, drag away.)

Pros of Skarner:

Not only a tank, not only a damage dealer. He's Flexible.
You have one of the best stuns/interrupt/supress in the game in you ult. You cancel channeled abiltiies with it, and if enemy champions have an ult that moves you, and you ult someone. You drag whoever you ulted WITH you. I've killed many an ADC when a poppy or Tristian ulted me away.
Your W gives you an engage or a disengage, but also a shield, it's extremely flexible.

Cons of Skarner:
Easy to Kite/CC as you have no Dash.
Skarner is fairly squishy early in the game, but has decent damage. So other burst champions tend to reduce to little or no health pre-6.
Skarner is hard to master, to fiqure out when is the right time to go in for the gank.

I'll be looking to get some videos together for you guys in the near future.

Until then, feel free to stop by my twitch, and ask me any questions!