Here is a video, I got my inspiration from. The video illustrates this Captain Teemo's role in the game, when playing it AD.
I hope you'll enjoy it :D
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Camouflage. If Teemo stands still and takes no action for 2 seconds, he becomes stealthed. After leaving stealth, Teemo gains the Element of Surprise, increasing his attack speed by 40% for 3 seconds.
Blinding Dart. Obscures an enemy's vision with a powerful venom, dealing damage to the target unit and causing all attacks to miss for the duration. Deals 80-260 (+0.8 per ability power) magic damage and causes the target to miss all of their attacks for 1.5-3.5 seconds.
Move Quick. Teemo scampers around, increasing his movement speed until he is struck by an enemy champion or turret. Toggle: Teemo's movement speed is increased by 15-35% until he is struck by an enemy champion or turret.
Toxic Shot. Each of Teemo's attacks will poison the target, dealing damage each second for 4 seconds. Teemo's basic attacks poison their target, dealing 8-35 (+0.14 per ability power) magical damage upon impact and again each second for 4 seconds.
Noxious Trap. Teemo places a explosive poisonous trap. If an enemy steps on the trap it will release a poisonous cloud, slowing enemies and damaging them over time. Uses a stored mushroom to place a trap which detonates if an enemy steps on it, spreading poison to nearby enemies which slows movement speed by 30/40/50% and deals 250/475/700 (+1 per ability power) magic damage over 4 seconds. Traps last 10 minutes. Teemo forages for a mushroom every 30/26/22 seconds, but he is only big enough to carry 3 at once.

Start with:

Then Go for:

You can buy another Dorens if you have a tough lane:

You Should also buy your tier 2 shoes at this point, you can go for:

Vs. CC and Magic, or go for either:

or

Then:

Then:

which is a great item in almost any game.

And the last item:

I prefer:

And the very last item:

Now you can sell your!:

And buy:

Vs. Physical Team, or you can buy

Vs. at Magic Team, or simply

or

or