Olaf is a melee jungler who should be able to kill the ad carry in the teamfights with his ultimate.
He is fast in the jungle and has a nice amount of damage and health points, who counters armor with his reckless swing.

I build armor pen marks, for strong ganks and a fast jungle.
My seals are for armor to be stronger in the jungle and tanky.
The glyphs are magic resist against the burst of the ap carry.
Quintessences are ad to be faster in the jungle too.

Standard jungle masteries, 21 in defense for strong jungle and 9 in offense to be faster.

We start as a normal jungler with cloth armor and pots.
The first time you back, buy boots and madreds razor, next time lantern and attackspeed boots.
Olafs W will make more damage for more hp, so we buy frozrn mallet, warmogs armor and sunfire cape.
The atmas is to make this buff stronger.
At the end you should sell the lantern for a bloodthirster, because this item is much stronger.

The priority is r->e->q->w because his e has a little burst and the q has a nice slow to be able to get in range for auto hits.

Smite for jungle and ghost to be able to run straight for the carry in teamfights, without any cc, because of ult.

Pros:
- No cc in ultimate to run away or catch someone.
- Nice slow because he can pick his axe up and throw it again.
- The burst of his e.
- Fast jungle, because of q damage and w sustain.

Cons:
- No cc, just a slow

U start at the blue buff, go to the wolves, wraiths and red buff. Remember to throw your axe just in front of u to pick it up and be able to throw it again. U try to gank bot, if its warded mid, and end with the double golems. U go back, buy boots and madreds razor, go straight to wolves and top.
U give the second blue buff to your mid lane and the red to ad carry if u already bought phage.

In the teamfights your focus should always be on the ad carry. If the enemy team starts ccing you, turn on ultimate and maybe ghost to be able to hit and slow the ad carry.
But remeber to not leave your carries alone, so if the enemy ad carry is not in range, try to help them out.

Olaf is a very strong and fast jungler with much ad.
He wont get any cc and has burst damage with e.
His main problem is that he does not have any cc at all. This makes him unable to catch someone up or help the team in fighs out.