After been tested some build posted here about garen, finally i ma de a conclusion about a good and functional build for garen, even if you see to much points at offensive three, with runes describe it in this build you will be fine and balanced.
With this build you will attack a lot as you will be able to defend very well.

The best defense, is a good attack", i recomend begin with Doran´s Blade, this will allow us to start with a good damage and even get our "firts blood". After this we need speed, so we go for Swiftness boots, this item will allow you move faster to attack or escape. Now we need more attack damage so we go for 2 Long´s Swords, to be able to get The Brutalizer depending how match is going at that moment, we can start build our infinity Edge, so we getor , all depends our gold farming, you can get one or both, to finally get our B.F Sword. when you get the necessary gold, go for Infinity Edge.
Its time to worrie about our defense, so for that we can get Giant´s Beltto get later our Sunfire Cap , if you still cant get the money for Sunfire, get Chain vest . once you get Sunfire Cape get another Giant´s Beltto finally get our Warmog´s Armor and the build will be complete. If still got time at match you can get Youmuu´s Bladeand finally the Black Cleaver .
Now if you see that your team is losing i recomend start building defense first, then attack, try to decide the best choice depending the moment.

My advice for this build is use spells exaust and flash, as our objective is kill a lot we can, is a good combination to avoid our prey escape

PROS

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*good inicial attack and thanks to "THE BRUTALIZER" and "SUNFIRE CAP" you will be able to farm with monster and minions
very quickly.

*great ammount of damage once you get the entire build.

*thanks ghost and courage skills you will able to escape fast in case you be in troubles.

CONS

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*Usually will be the enemy target due your damage and defense.

*not much velocity movement.

*some build items can be hard to obtain at early game if you dont have a good team or has been killed to much.