This is my first guide and any help or comments, good or bad are greatly appreciated.

Garen is my first and only love. I have tried every champion but seem to always fall back to him. He gets a lot of criticism for being "easy" to play however that comes mostly from people who have never taken the time to really learn how complex Garen actually is. Early game he is probably the most dominating champion with massive damage output a silence that seems to last forever to enemies and a heal that frustrates anyone he faces. Late game however can get very tricky especially if you were unable to get fed early. Hope this guide helps!

Runes are basically the same if you're going Tank or AD as early game is played the same no matter what you want the extra resistances to help you last longer while your spinning out of your mind. Late game AD wont do a whole lot of damage to anything other than super squishes so the more Tanky you go will help your team more.

Garen masteries have all sorts of possibilities and you just have to find what works best for you. I have used this set up for most games and it seems to work best for me though I am always experimenting with alternative strategies. Obviously any Tank wants mostly defense masteries and an AD will want mostly offensive masteries but once you have your core set up there are always a few masteries left and that is where the personalization comes in.

Tank- I max every tanky mastery putting an addition 1 into each of my spells and one into time spent dead as that can really help your team. The tank needs to be there for every team fight, not spend the whole game dead.

AD- I max every AD mastery and give myself a little extra armor and MR for the early game survivability. Again putting the extra points into my spells and one into time spent dead. I also have that one point in turret damage, most people don't do this but I find that Garen is surprisingly good at destroying turrets. Judgement doesn't do any damage to them but Decisive Strike does a ton and that little extra damage will destroy a turret just that much faster.

Items are very liable to change based on who you are playing and how the game is going. If the other team is heavy AD you will want a Thornmail and may not need the Force of Nature. As you play more you will learn what works best for Garen but this is a very good and well balanced starting guide.

AD build usually means that you either have to win the game very early or switch to Tank as late game damage is very small. I always start with the stacked dorans blades for the health and damage output for a very small fee. No champion can stand one on one with garen when he has all 3 at lvl 6. After the BF sword will many times be gg as you will just do too much damage to handle. IE and FM are typically as far as I get into this build when playing because one team will surrender by this time. However if they want a slaughter Last Whisper will give that to them. For late game atma's and Warmogs are the only way to go for an AD Garen, giving you an extra damage and a ton of health.

Feel free to change whatever you see fit but also give mine a try, you just might like it.

Skill sequence goes a little like this.

Lvl 1: Spin to Win, judgment thier ***es and show no mercy.
Lvl 2: Silence them, Spin to win. FB easy

After Lvl 2 you can decide when to get your courage and just put one point in. Then max Judgement then, Decisive Strike and finally Courage, Putting one point into ult asap. Lvl 6,11,16.

Know that Decisive strike will still go off even after the sprint buff wears off you still have 1.5 seconds to attack.

Pros:
-Early game dominance
-Super Silence
-Turret pusher and Tank
-No mana

Cons:
-Weak late game
-If silenced is useless
-Cant kill super minions

Always lead with silence, even if thats all you can hit and then have to run, still a good damage poke, to champ or turret. When fighting lane let ranged get minions and just absorb the xp and hide in the bush. You will almost always be more pushed than the other team and if they dont have a ward up you want to get as close to the enemy as possible just waiting to silence and spin to poke. When you get someone low you dont want to flash and chase, instead let them hang around and when you see your chance flash out of the bush on top of them using silence at the same time and spin, this is a 1,2,3 combo that will not only get you the kill but scare the **** out of them and possibly cause them to break their keyboard from trying to use spells that they cant cus of your instant silence. Try and save your flash for this every time.

Late game use your courage and silence as much as you can while you are tanking. Keep a look out for low health champs in team fights as your ult does more damage the lower their health. Always try and get it off if you are tageted as well. It will just about be up by the time you get back to your team and any help you can do is better.

Keep practicing, any champ takes a while to master and though people think Garen is simple a mastered Garen can easily carry.