Never lost with this Garen build, tested a lot...
Start Dorans Shield and Health Potion. ALWAYS make your first build Sunfire Cape, next (in no particular order...) Boots of Swiftness, The Black Cleaver, Spirit Visage, Warmogs Armor, Infinity Edge. This gives you the Garen carry, to carry ANY team. I have carried so many feeders/sucky players with this Garen build and have NEVER lost with it. I have successfully beaten Teemo, Jayce, and many other anti's (vs. Teemo you just flash then use abilities to get to him early game...). If you are wondering about how to win vs. a specific champion please let me know, I have probably done it. Basically though you just hit your q then e, if hard engaging use w. I usually run Flash and Teleport, but depending on my team composition I run Teleport and Ghost.
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is worth getting every game.
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is the dullest lane ever...
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when the game ended.
is a great tool for chasing pantheon after he uses his stun on you. Pantheon has amazing poke, and he can deal effective damage, but after he uses his stun and mini spears, you can chase him down... hiding in a bush is also a great tactic in top lane. Try to go at him from the bush when he goes in for cs, make sure though (especially at early game!) that you won't take much minion damage. You can rush in with your q/e combo, and although your q will be blocked by his passive, it should still silence him, and your e will deal massive damage while sunfire cape is also doing stuff... You should be able to beat Pantheon with this, especially if he goes with some HP as your ultimate will do extra damage when his HP is drained... By the way I always try to look at my opponent's health and figure out when my ult will get the kill so that I don't waste it.
or
when your at full build, your choice, and dice through anybody who thinks they can take you on.