i like the swiftness, warmog's, and atma's but after that i wing it
force of nature against an ap heavy team, thornmail against ad, obvious stuff

I approve of your build, however I DO NOT approve of your iteming order. I main Garen, play him quite often. I have mirrored against several Garens who rushed Warmogs and I have DESTROYED them all with just Merc Treads and Sunfire cape. Warmogs and Atma's a great items for Garen, but should be built LATE game.

Every Garen needs to rush boots. Boots make him able to deal insanse amount of damage. And Warmogs is a bad item for Garen, it costs to much and only gives you hp and stacking it requieres a long time. I would rather go for Sunfire Cape+Force of Nature, cause Guardian Angel is a very situational item and shouldn't be build if you don't dominate. Also, Sunfire Cape is the best item for Garen^^.

What are your thoughts on the ghostblade? is that still a legit item for garen, cause i know i see it in a lot of other builds. i think i like yours the best, with the exception of possibly adding the ghostblade for some item. though i am a new garen player, so feel free to set me straight. :)

Played 1 time and had stats 8/0/7. Great build, that's why I think tank Garen is the best Garen ^.^

Build lacks severe damage capabilities. Bigger punching bag, low damage and easiest to hit. Critical damage are always based on random chance and no guarantees, so do not mind not seeing them in your build. Maybe try changing out your Q runes with more armor penetration.

great build only thing i changed was i swapped out boots of swiftness and went with berserkers greaves. i like them better. other then that +1

Very good build. Way better than any other there are. Let's face it: Garen is not really top pick, but with recent buffs at least he's fun to play again. A few changes I would made:
For blues I usually go Mres. The final build has got impressive armor thanks to Atma and GA, but lacks a little bit of Mres, especially in early game.
For yellows I take dodge: these prove invaluable against other physical dps, really provide more of an edge. Quints and HP yellows provide around 4AD from Atma so it's not a big deal.
For quints I take Arpen - to reduce Armor as much as possible is the best bet on Garen.

Considering masteries: everything perfect, except I would take this final point in offense for Mpen, just for the ulti.

Items are the best I could find - no other build does better.

Summoner spells - sometimes I choose Flash over Ghost, but it's up to personal preference I think. Ignite, imo, is dead weight late game, while exhaust not.

I vote thumbs up and I hope I see more Garens utilizing this build, not the ancient Sunfire ones or straight tank/dps.

Oh and btw: from the 20 or so games I played with Garen this year, I think I bought swiftness 2 or 3 times. -CC on Mercs is too good to pass up, I would put them in the primary build instead of swift and put swift in other options in the guide.

Like the build

Replace that last phantom dancer with a Last Whisper. Its a much better choice.

Im not sure what to think about this build. I think I'd have to try it to figure it out.

Alright :) I will this weekend, probably after New Years since I work tonight and tomorrow. Thanks for the input everyone, glad you're having success :)