like, pretty much this, ward your jungle, give your lanes more time to react than theirs, remember that the enemy team is slow to react too probably
Sejuani has the weakest early game of any traditional jungler in the game. Her first clear is mortifying and she has no tools to deal with early invades because her sustain is garbage. I would rather be Amumu, who doesn't have anywhere near the issues that Sejuani and Nautilus do.
For sej and naut, their early clears are so weak that they need to rely heavily on ability usage for clearing. Naut is weak to invades because it's easy to abuse the shield being down. with both, it always comes down to appropriately using your trinket. It's easy to say you have an escape on Sejuani but you need to use Q to clear, and then it's not up for another 15 seconds.
I understand, to play "non-meta" junglers you have to be very competent at them and understand their weaknesses far more than you would a "meta" jungler. Ya'll are kind of making the same point I am. The non-meta junglers have a rougher time of it. You have to be so much better at them as a champion than you would a point and click jungler like Pantheon or Xin.
I feel comfortable on Sejuani as a non-meta jungler because I've played so many games with her. I know what I can and cannot do early game with her and I rarely have bad games where I'm completely crushed by the opponent jungler. Put me on Fiddle and it'd be a completely different ballgame.
However, I played Pantheon for the first time and it's the easiest thing in the world. Heck, I stomped as a Warwick feral flare last night. I've played Warwick all of 3 times.