I don't like doing Mini damage with Olaf so I rush Strong items. With out like steal Olaf is Olaf. But I like To be the top dog in the game. Meaning that If I am not Strong I will make sure to Get Items to mess with my enemy. Olaf is a Tanky Dps champion that deals a lot of damage. He is one to get in a Team fight And Focus anyone and kill them under 10 seconds. I don't mind If I die in the progress, but I will die taking 3 enemies with me.

For my Runes I focus on Survival ability mainly. When I go in a lane I Often pick up first blood because of my burst damage and My insane health at level One(1).

For marks It's good to Have Armor Pen or attack Damage your choice.

Seals is simple to figure out, You Pick out Armor or Health.

Glyphs Is a choice that you have to make for your self in many cases. You can go magic resistance, Cooldowns, Magic resistance per level or Attack speed.

Do not count on your mana that much. Olaf Drains mana so fast you might not be able to do anything early game. So idea itemize on that or pick up Flat Mana Regeneration on seals or Glyphs.

I want to be tanky and dangerous at the beginning. If I own my lane early I can gank lanes with out jungle. I want my defence Tree to be almost defence mainly. Offence Tree Needs to be more Offensive.

Masteries is your choice really. I don't know about many of your ideas but I rather take away ghost and add in Flash.

I don't mind the cleanse but I could swamp that for Exhaust.

Do not pick useless Summoners.