Well, there are a few different rune pages but the current one I run:
9x Marks of Attack speed - Her spider form's passive gives her lifesteal, her W is basically xin zhao if you're familiar with him. AS gives you better dueling and Jg substain.
3x Quints of AP - You're a burst champ, so do damage.
9x Seals of Armor - Any jungler should be using these
9x Glyphs of AP - This is to also add to your immidiate early game burst, what you achieve in your early game changes the rest of the game, so hit hard during this time. elise also falls off mid/late game so while you're overwhelming for your level, do damage.
The other options people run would be:
9x Marks of Magic Pen - to get past early game Magic resist runes - This is ok but I feel like having substain with lifesteal+attack speed can make or break a 1v1/clear camps better.
3x Quints of AP - same as earlier
9x Seals of Armor - Same
9x Glyph of Flat/Scaling Magic Resist - Give you a little bulk and take enemy AP hits better, scaling more for late game since elise usually goes AP off tank. I pref flat AP cause doing damage early is important. That little MR isn't going to help you burst something down as easy, clear camps any easier, and bringing scaling MR just adds bulk to late game, in which you fall flat and become basically a second support anyway in the late game.
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Also remember to let your spiders take the monster camp hits. Take like 2 auto attack from the monsters, then let the spiders take the rest while you heal off the previous damage. Just do a quick click back and then right in for the spiders to aggro the hits.
Since you're still learning elise you might want to go with the second rune page mentioned... mine is more on the aggressive side and you might not be able to be that aggressive without a lot more practice with her as a champion.