I have been playing Morgana for a while now and I am unsure as to what runes to use. I play a dps aggressive style. I am only level 24 so I don't have all the rune slots available yet but i am working towards getting them all. Do i go all cool downs, ability power, a mixture of both? Please help!

Magic Pen is better than AP. So stacking MP isn't a bad idea.

Work on getting 6% CDR with runes, 9% from Masteries, and then the last 25% from Golem/Items.

She's Tanky so the rest could go with Health, Dodge, or even run speed Quints if you wanted.