Hi everyone, I'm publishing my second build and my first guide here on MOBAfire. I'll teach you how to play with this build.
Please, remember to vote on the guide and let a comment about what you think about this guide. Thank you.

MARKS
I chose marks to put my armor penetration runes because it gives me +15 of Armor Pen. and that is very good at early game.

SEALS and GLYPHS
A lot of people thinks that if you use Attack Damage per level, you will have a small amount of atk. damage at the start. That's true, but if we pick 9x runes (Seals and Glyphs) of atk. damage per lvl. we will have a very nice attack early and late game.

QUINTESSENCES
With 9x Mark runes of armor pen. we will have +15. If we use them with 3x Quintessences, we'll have +25 armor penetration at the start. Belive me, that's a lot.

I focused 23 points of masteries on offense tree because those points will help you when hitting an enemy, it'll be very efficient.
In defense tree, I picked 3 points on magic resistance and armor so you can have little help with defense.
The point that it is left, I put it on the total health and mana regeneration (Utility tree).

Doran's Blade first is a very good item, gives you +100 Health, +10 Attack Damage and 3% Life Steal. Remember to sell it later for a better item.

In fact, you can pick Berserker's Greaves (good attack speed and normal movement for a boot) or Boots of Swiftness (very good movement speed). But I prefer Berserker's Greaves just for the attack speed bonus.

Most people choose Attack Speed items first, obviosly for the attack speed. But it's better to pick a good damage before you got atk. speed while you're building a DPS build. Remember: pick damage, and get atk speed asap. That's just why I got Phantom Dance next.

Using Panthom Dancer will give you +55% Attack Speed, +30% Critical Strike and +15% Movement Speed. Combines with Infinity Edge perfectly.

The Bloodthirstier guarantees +60 Attack Damage +15% Lifesteal. Passive: Gain an additional 1 Physical Damage and 0.25% Lifesteal per kill. Maximum of +40 Damage and 10% Lifesteal. It is essencial to have life steal in every DPS champion. Bloodthistier offers 100 Atk. Damage (when your passive is maximized) and 25% life steal.

Frozen Mallet is a very good item to combinate with atk. speed and damage. Because you got a good chance to slow the enemy and deal a great damage to him. And also gives you +700 Health. Change Frozen Mallet for Madred's Bloodrazor is also a good option with Last Whisperer to kill bruisers/fighters or tank champions.

Last Whisperer. Is an optional item, you use it when you want to atack tankers, bruisers or another champion that may have high def. +

And Finally the elixir. Pick them especially late game, when your build is complete and you have money left.

PS:. You can use Frozen Mallet as a Survivor item. Another reason to use it with Teemo.

I recommend you to use Exhaust for some reasons:
You can use exhaust to slow your enemies and to reduce the damage that he can deal to you or your alies. That would help a lot.
I like flash because I can use it to escape from a bad situation or run to the enemy.
Flash and exhaust are very good together. Especially if you wanna kill an enemy.

Remember to use your Blinding Dart on attack enemy carries.
Get red buffs, they give you extra damage and it is really good.
Ward with your mushrooms: Baron, Dragon, blue and red buffs.
Put a mushroom right under Teemo and wait there if you know that an enemy will pass there few seconds after.

That's all. Thank you guys and remember:
TEEMO RULES!
;)