Hello there my name is "Anaphros" and this the way i like to play with olaf...critical strike!!!
I know is weird to see an off-tank/DPS champion with AD items (hey i've seen olaf with trinity force) so here you can see the item build, the runes i use, my skill build (maybe i've done something wrong) and the masteries...

The runes i used were based on an other item build that i used to use (and still do) with items that gives olaf armor penetration. I got my marks armor pene. , my seals hp per lvl , my glyphs cd reduc. and my Quintessence armor pene. because as i mentioned it was armor pene item build.

Now here is, i can say, the most important thing u need to know.

1st of all approximetely if u manage to get all your item build you would be able to deal 900 dmg as critical strike + with your armor pene (wich would be abou 61) you deal great ammount of dmg. 2nd atma's impaler passive + your hp (wich would be about 3600+ at the end) + all the other dmg items u get 300 dmg and if u use your visious strike you dmg is boosted up to 380.


Now the bad things with this item build:
1st and most important thing to know is that YOU ARE NOT AN OFF/TANK DESPITE YOUR HP. You die so easy (mostly early in game) like a wall o paper burns. So dont do "rambo" style things at the begining.
2nd Till you get your Stark's fervor you are COMPLETELY based on your visious strike for living and killing.

Here is one thing to know to use this item build properly:
1. DONT dive till you get warmog's armor and infinity edge!
2. TRY to get 1v1 combat and the spells MUST be ready to use them
3. GOOD LUCK AND PM ME FOR ANY QUESTIONS YOU HAVE ON THE ITEMS,SKILL,MASTERIES BUILD.