Been having a lot of success with Skarner jungle (building Triforce). Saw he was very high winrate and tried him out, so thought I'd write up some advice if anyone else wants to try him. The best option, I think, is to go with knife/3 pots and go with a full clear to start (Gromp (Smite) -> Blue -> Wolves -> Raptors -> Red (Smite) -> Krugs (Smite if needed)), unless you really need to do something else. With any kind of help you'll have no pots but be pretty healthy with red buff, at level 4 (at least 400HP). Make sure you put a second point in Q at level 3 as it speeds up your clear more than E. If you grab the scuttle crab near you you'll be able to get Stalker's Blade + Boots on your first back, likely ahead of the other jungler. Going back through Gromp -> Wolves -> Raptors will get you to level 5, 200xp short of level 6. That xp has to be picked up from lane creeps, kills/assists, or a raid on the enemy jungle if you want your ult fast.
I like to just skip Cinderhulk for the time being and head for Phage and upgraded boots. You don't need Bami's Cinder to kill camps quickly as Skarner, and it's quite a lot of gold (1100) for 280HP. The key is keeping your level high to remain hard to kill, especially when you start putting points in shield. With Sheen/Triforce you pack a serious punch if anyone tries to fight you or when ganking, and you're surprisingly tanky. As the game goes on you transition more towards peeling, with E and R. Once you get T-Force and Cinderhulk, go for generic tanky stuff like Randuin's/Dead Man's Plate/Frozen Heart/GA/Spirit Visage as needed. If you are the main engager, make sure you know who has Flash/QSS as the game goes on - you can throw the game by wasting your ult in a later teamfight.
Runes: AD/Arm/CDR/AS (can swap for AS reds, or for MR blues)
Masteries: 12/0/18 (Strength of Ages)