*Update*
I have been playing a lot more and found that the tanky items i had previously recommended are not as useful at this point. I have adjusted the guide by going with tank runes and offensive talents.

Hey, this is the first build I am doing and it works pretty well for me. The key point and success of this build is to have lots of damage and health and run around killing during the end game.

An ideal team composition is just the one with skilled players and balanced damage.
i.e. Vlad would go mid, Akali and Olaf would go together and Blitz and Ashe would take the other lane.
Also you should lane nearest to the blue buff.

And if u view this please vote on it. Please.

Pros:
-Very high health for a melee dps champ
-Very high damage considering the number of HP items
-Hard to Gank
-can carry team mid to end game
Cons:
-Item dependent
-Susceptible to CC early game
-requires the team to not feed a ridiculous amount
-WEARS NO PANTS!!!!

Ok, so runes. The runes are very simple: Armor, Magic Resist and Health. All combined gives you enough surviveabilty early on to make the enemy curse you since your E will do ridiculous amounts of damage and you can soak it up. DO NOT MAKE THE MISTAKE OF THINKING THESE WILL PROTECT YOU END GAME. The two starter items will give you enough tankiness to survive unless you really need help in which case go for build 2 but it is not as much damage oriented.

Ok, so defensive runes and offensive masteries. These masteries max out Olaf's carry aspect of using his regular attack to do the most damage. You want to attack more and for more damage and the masteries do just that.

So ability order. The simple version is this: R > E > W > Q
So get your ult whenever you can.
Then max your true damage strike next.
You W gives bonus damage and lifesteal so it is next.
And you slow does the least damage but costs the most so it is the last ability to be maxed.
Of course you want one rank in Q so that ganking and killing is easier. Try to get with a partner who can get a lvl 1 stun or slow so that you can go for first blood.

Ghost -- more movement =D this just makes getting around easier.
Exhaust -- stop the enemy from running and lower the damage they do. *REQUIRED*
Ignite -- do more damage and stop them from healing. Usefull if you team needs more damage.
-- should only be taken in extreme cases!
Any other spell is too utility or jungle based.
*Notice how Utility Mastery makes your Blue buff last longer.*

The basic theme is that you have to buy the Tier 2 items in order to be effective mid game. Rushing Frozen Mallet SUCKS!!!! The basic idea here is to have minor tankiness(with Treads and Lantern) then go for damage/crit with Zeal and Brutalizer and finish with movement control on Mallet and Ghostblade. The Dancer and Edge are your two big damage items and you should buy them at you discretion.

These items are for when you become the tank either because your team did not grab one or they are failing horribly. Your damage will be nonexistant but you will be able to tank more. Sunfire + Atma's + Mallet = the only real damage you will do.

So the main point of this build is mobility! Your Q and Frozen Mallet and Exhaust slow. Ghost and Youmuu's speed you up. Then your Ult and Banshee's block CC and one ability. You should never be bogged down or ganked unless 4 or more come at you. This annoys the other team because you will go in kill and then run away before they can catch you. And then you do it again.

Have Fun and Happy Killing =D