Garen Hp Tank

This build is to tank and support your team while at the same time getting kills. With this you will have so much Hp no one on the enemy team will be able to kill you and your only deaths( if any) will be at early game gank.

Pros
Massive Hp
High Armor/Magic Res.
Great early game killer
Cooldown based champ
silence ability
Great movement
stops slows with judgment
increased movement with Decisive Strike

Cons
Cooldown dependent
Melee based

For runes i use 0/21/9 because i love going full defense when i play tank characters giving me best chance for survival.

Flash Give you the chance to get right in there face when they try to run from you or you can use it to flash away in case you see a gank coming.

Exhaust You can exhaust them from getting away from you while your in judgment. is also good for first gank giving the enemy no chance for survival.

or

Cleanse great spell removes slows and stuns great for any melee based champ.

You could also use ghost, Ignite, and heal depending on how you like to play but i do not recommend any of them most the time your enemy gets away.

skillsPerseverance - Garen will regenerate 0.5% of his maximum health per second after not receiving damage for 7 seconds.

This is the best passive ever in my opinion the more hp you have the more hp u can regenerate making you never have to go back to your base unless you need to visit the shop or die.
Decisive Strike - Garen gains a 15 / 20 / 25 / 30 / 35% speed boost for 3 seconds. His next attack deals 150% of his base damage plus 30 / 45 / 60 / 75 / 90 bonus damage and silences his target for 2.5 seconds.

love this ability gives you a speed boost to chase an enemy down and also gives u a silence so they cannot use an ability and at the same time it damages the target its a 3 in 1 combo great ability.
Courage - Passive: Garen's armor and magic resist are permanently increased by 0.5 every time he kills an enemy unit. This bonus is maxed at 5 / 10 / 15 / 20 / 25.

Active: Garen places a defensive shield on himself for the next 3 seconds, decreasing all damage taken by 10 / 15 / 20 / 25 / 30%.

Amazing ability gives you Armor and magic resist and a shield that decreases all damage makes any 1v1 fight winnable and makes you survive a gank every time.
judgement - Garen rapidly spins his sword around his body for 3 seconds, reducing the duration of slows by 50% and dealing 60 / 100 / 140 / 180 / 220 (+120% of his bonus Attack Damage) physical damage to nearby enemies every second. Garen removes any slow effects on him at the start of the dance.

The bonus damage is further increased by Garen's critical strike chance. Damage to minions is reduced by 50%. This cannot damage invisible minions or wards.

This is a great ability gives you the chance to stop a slow and reduces damage by minions giving you a great opportunity to kill a champion in a horde of minions.
Demacian Justice - Garen calls upon the might of Demacia to attempt to execute an enemy champion, dealing 175 / 350 / 525 damage plus 1 damage for every 3.5 / 3 / 2.5 health they are missing.

Great skill to finish off an opponent if it comes down to the last "Tid-Bits" of a fight or you can use it to ks someone for a free kill. gives u range and can be pre-cast while using another 1 of your abilities.

Early Game
With this build u go straight support tank while at the same time doing a good amount of damage.To start off get a Ruby Crystal then head to your lane. once you get about level 4 (depending on how many minions/champ kills you have) you should have enough to get your
Boots of Speed/Boots of Swiftness by level 6 you should have enough for Chain Vest once u have this u should not be dieing at all unless you get ganked by the whole team. At level 10-11 you should have enough for Guardian Angel.

Mid Game
by now your team should have pushed some turrents and be in middle lane. Once in middle lane will be good on gold with Guardian Angel you should die and you should have alot of Kills/Assists once you have enough for Warmog's Armor you should be about lvl 11-12 with over 3,000Hp. Just keep getting Kills/Assists until u have enough for your Sunfire Cape.Now you will have enough hp and Damage so you should be getting kills instead of assists.

End Game
by now you should be lvl 16-18 with Warmog's, Boots of swiftness, guardian Angel, and another Warmog's/ or a full build. You should have close to 4-5k hp and be able to tank turrents for your team to win.