There was once a little scorpion called Skarner, who used to lane freely in the Crystal Star, Then came along the Misters and Misses Of Magic, unleashing chaotic magic in Runeterra, making little Skarner feel sick, so little Skarner dug and dug with his friends until he was under the ground, and then he went to sleep.
Zzzzzzzzzz....Oh where am I? Skarner looked up and saw a big blue golem standing, taunting little skarner. Skarner may be little, but he had a big stinger. He stung and stung, and the golem lay before him, dead.
Then Skarner realized he belonged to the jungle, so he lived there happily ever after.

Go for all greater runes, cuz well they're epic, and Skarner cant jungle without them.
5 Marks of Strength for the bonus +5 AD
4 Marks of Alacrity for +4% attack speed
9 Greater Seal Of Resilience, Since you're jungling, the 13 Armor gonna help loads
9 Greater Glyphs Of Potency, Oh you're playing a ****in AP tank fgs.
3 Quints Of Potency, AP anyone
(You can get movespeed quints, but I dont really think I need them)

21 in Offense, You're not going tank, keep that in mind
9 In defense, Your jungling, need some defense, so +6 armor, bladed armor to return dmg to small creeps, 2 in tough skin, Jungle again, and vigor, which reduces your need for a regrowth so you can get more pots and cloth armor.

Start with Cloth Armor, and five pots.
Jungle till level 5,and then go back for greaves (greaves ake your clear faster, and makes it easier to spam your passive
( Change greaves for treads late game if enemy team is cc and ap heavy, or Tabi for auto attackers )
Second back, get at least one good gank, dont go back until you get a kill or until you die, Get Sap Cryst and Ruby Cryst (Sap first for more mana), Then make it catalyst and then complete RoA
Save up for a NL Rod, but dont build it further.
Next aim for sheen and then lich bane.
Change your needlessly large rod to a deathcap
Nashor's tooth for the bonus ap and passive proc
(Get Malady if you're not getting kills as it costs a lot less )
Rylais, Cuz forever slow with your Q is just too OP.
( Last Build )
If you got free gold,
Sell your Malady/Nashors and get Zhonyas, More sustain, allows for anti carry skirmishes.
More Gold? Get Elixirs, All Of them (You benifit from all)

Dont criticize me, but I always go for my e first, with the runes and masteries, Its just too good
Start by three auto, then e.
Super heal
With the runes, you'll have it up in three secs, this way, you can solo blue with only one pot, Dont try if you dont have runes specified ( in which case go for q first)
Lev 2, get the shield, 20% attack speed helps loads. and a shield, Oh goody
Lev 3, Another point in fract, or Q
Further follow the skill sequence
(Max q first for fast jungle clear, or e first for epic ganks, One point in q just for the slow)

Ghost/ Flash,
Flash in and ult, Ult and flash to turret
Ghost in, ult, ghost out to team
Take whatever you want

Smite
You want to steal their baron? TAKE IT, TAKE IT CUZ YOU A JUNGLA

YOU BE OP NIGGA.
If you dont like this build, we got loads others.
Im just giving a different build, because everyone goes for max q first, while i go for a lot of dmg with e. Also, you'll have +3000 health, so you can tank most of the dmg dealt, while still doing **** tons of dmg.
Tele Out.