How to build ur teemo resource

At build 1 I take Apen Marks for the early game damage armor seals for early game mr gylhps for early game and flat damage quints for early game

At build 2 Mpen marks and quints for dot poison alacrity seals for attack speed and mr gylhps for those heavy ap

At build 3 Mpen marks and quints for dot poison and mushs clarity seals for mp regen and ap per lvl gylphs for late game ap

At build 1 Masteries are the normal for ad dps

At build 2 Masteries are for early game survive and mpen

At build 3 masteries are the normal for ap

At build 1 i take wriggles for def life steal and damage early game, berzerker boots for attack speed, cleaver for armor pen, phantom for movement and attack speed, infinty to maximize
ur damage and banshee for magic resist and hp

At build 2 i take madreds and boots for early game farm and movement, malady for damage, wits end for mid game damage, now i get madred bloodrazor for those champions with hp but without magic resist, frozen mallet and rilay for hp and slow

At build 3 i take boots and rilay for hp and slow then i grab an abbyscal scepter for the aura and the ability power, i get rabadon death cap for the passive and ability power, void staff for magic pen and zhonya for armor and ability power

At build 1 i get flash and ignite because i already got movement speed from dancer and my w

At build 2 i get ghost and ignite for run and chase

At build 3 i get flash and ignite because i ever use them on mages

Pros:
Hellacious damage (if you follow this build)
One of the best farmers in the entire game (yes, I am looking at you mushrooms)
Nice early game, fantastic mid game, lethal (to the enemies) late game (if you follow this build)
Good pushing abilities
Tank destroyer
Can evolve into a fully capable assasin late game
Can give map control to his team, which determines games
Mushrooms deal very good damage

Cons:
Quite squishy (though this build has been designed with his squishiness in mind, and attempts to counter it)
Mushrooms can be destroyed by anyone who has an oracle's elixir (in fact, in ranked/normal games every roamer will have an "eye" so a good team, with a good support who destroys your mushrooms will have you crippled as far as your team utility is concerned. Oh and btw even melee champs can clear your shrooms with an oracle's, as it doesn't need someone to come close for it to detonate, but to step on it.)
Has a tendency to be focused in team fights
Low health points
If your team has a lot of ap champs, and enemies build heavy magic resistance, you may begin to have some problems.

My first guide sorry for the english but i am spanish