This is the Olaf build i played a long time with and i finally found the time to share it with you!
This guide will lead you to victory in any battle.
It is made for high damage output but good survivability.

PROS:
+ Olaf is an awesome laner ( that's the way i play him).
+ I personally prefer him playing top lane because of his nice harassment skill and his very high damage output even though you play him on survivability.

CONS:
- In my opinion the only cons of Olaf are, that he CAN be countered with items like Madreds Bloodrazor or Thornmail.

The Runes im using are:
9x dmg Mark
to do tons of damage on early game...
9x Armor seal
...but still having some crazy protection
9x Armor Glyph
3x Atk speed quintessence
It sometimes happen that you have to face one on one in the early game and 13 attack speed are quiet helpful.

It took me quiet some time to figure out which items to buy and when to buy them.( almost two hours at nature science course ^^)
I build Wriggleys Lantern first because this guide is for the top lane and because you are alone and you always might be ganked you have infinite free wards with this item, some damage and armor AND you are able to last hit minions in a stylish way(20% chance to deal 300 dmg!!!)
The Berzerkers boots are the perfect boots for Olaf because some base attack speed is always useful, especially in early game when you last hit minions.
Then i build frozen mallet with Phage first to deal some damage, get some base health and because at this phase of game you might fight the one and other and he might try to run away, but you phage MIGHT slow him and you kill him. As soon as you have the Mallet, you are almost unstoppable because you have 700!!!!! + health and you slow him EVERY TIME you hit the opponent.
Because you have tone of life and in this face approx 2500 of it you will instantly get 40 extra damage besides the 45 armor and 18% crit chance.
As soon as you got Infinity Edge, you are the biggest bad *** is town because of +80 damage, and +25% crit (now you have 43% crit) and the crits now make 250% dmg!!! which is almost 700!!.
And with phantom dance you are Odin himself!!
55% extra attack speed ( now you have 80%!!!! + your passive which are 130% at half life)
then +30% crit chance ( now you have 73!!!!%) and 12% movement speed.

After i made my item build i showed some math skills and here you are:
+165 dmg
+15% life steal
+700 HP
+75 Armor
+73% crit!
+80% attack speed (without passive)
12% move speed
free wards and slow on basic hit!!

plus the base stats that makes:
~280 dmg
15% life steal
~3000HP
~200 Armor + 50 Ulti
~100 M.res + 50 Ulti
73% crit
80% attack speed
+12& move speed
free wards, slow on basic hit!

I take Q first to be able to harass and to take minion kills if i get a strong ranged caster.
Then i max E first because as soon as i slowed him with the axe i run over to him and kill him almost instantly because the E really does tons of damage as true damage.
I only take W as 4th ability and max last because the E should have strong base damage and W is just useful for 1 vs 1 fights which rarely happen in early game and to steal some life from the minions but you wont need it because of the vampiric scepter i buy in early game.

In my opinion ignite and flash are a marvelous combination.

It often happens to me that you almost kill someone and he gets away with ~ 50-100 life.
In that moments i could slam my head against the wall. So we don't want that to happen and that's why you should take ignite.

And sometimes (if your team is very bad 'sarcastic smile') you are overwhelmed and you know that you will die, but suddenly you see a wall to separate the lane and the jungle. So you use your ultimate, sprint to the wall and flash away!!! and the other team slams their heads against the wall ^^

Olaf is one of the most versatile champions in the LoL universe and my absolute favorite champion. But hes only strong, if you play him the right way which took me a long time to figure out how.
I'm happy to share my experience with you and hope to see you in battle one day.
Olaf vs Olaf ^^

If you liked my small guide to the strong bruiser Olaf please vote " helpful " and comment if you got any questions or tips.