Teemo is a legend among his yordle brothers and sisters in Bandle City. As far as yordles are concerned, there is something just slightly off about him. While Teemo enjoys the companionship of other yordles, he also insists on frequent solo missions in the ongoing defense of Bandle City. Despite his genuinely warm personality, something switches off inside Teemo's mind during combat so that the lives he must end while on patrol do not burden him. Even as a young recruit, the drill instructors and other trainees found it a little disconcerting that, while Teemo was normally charming and kind, he turned deadly serious and highly efficient the minute combat exercises began. Teemo's superiors quickly steered him toward the Scouts of the Mothership, which is one of Bandle City's most distinguished Special Forces unit alongside the Megling Commandos.
While most yordles do not handle solo scouting missions with a great deal of finesse, Teemo is remarkably efficient at them. His record of success in defending Bandle City from infiltrators easily makes him one of the most dangerous yordles alive, though you'd never know it by having a cup of honey mead with him at his favorite inn. Bandle City chose Teemo as their first champion for the League, and he has taken to it like a duck to water. His signature weapon - a blowgun - uses a rare ajunta poison he personally gathers from the jungles of ***ungu. To help cope with his lengthy periods of isolation, Teemo recently struck up a friendship with Tristana, a fellow League champion and fellow member of Bandle City's Special Forces. This connection is healthy for both yordles, though now Valoran's voracious media outlets circulate rumors that the friendship is turning into a romantic relationship. Regardless, Teemo is a crowd favorite in the League of Legends, and a pint-sized foe that many have come to fear.

The runes I used in this build are purely for damage and a little bit of defence. That little bit of magic resist helps Teemo become a little less squishy and helps him be able to gank allot easier and survive in lanes.

The masteries focus on more defensive aspects, trying to get as much survivability as possible. It seems to work, and helps me stay in lane and not get hit as hard in team fights or whilst escaping from close assaults and ganks.

One build route for Teemo is the physical damage route Which I have shown in this build; This route takes advantage of Teemo's innately fast attack speed and quick attack animation along with the attack speed boost his innate ability provides. This involves getting items which boost attack damage and attack speed, such as; Malady, Madred's Bloodrazor and Nashor's tooth . Move Quick is utilized in order to keep up with fleeing targets.

Sometimes it is better to stand still and go into Camouflage for an escape mechanism than to use Move Quick or Recall.
Blinding Dart can be used to harass effectively and can help Teemo kill physical champions in fights.
Blinding Dart with Exhaust can destroy a champion who relies heavily on physical attacks like Tryndamere or Caitlyn. Apply exhaust or the blind first, then the other after that has worn off. If you use both at the same time, the blind will override the AD/AP reduction. Similarly, you can use these two abilities on two champions, effectively taking them out of the battle for a few seconds.
Blinding Dart resets the attack timer when used, which allows 2 rapid-fire attacks. This is extremely important to learn how to use throughout the game. Opening with a normal attack, immediately using Blinding Dart, then proceeding to autoattack will apply great burst damage, even during laning. Try mastering this combo to use it on the fly and you'll increase your AP/AS damage tremendously.
Use Move Quick to get back to lane quicker.
Using Ignite with your poison can ensure you kills.
One strategy is to place some Noxious Trap in your lane and wait for the enemy to push. After this, go into Camouflage. Then, after the enemy runs into a couple of Noxious Traps, use Blinding Dart and auto attacks to finish them.
Placing a Noxious Trap or two behind the first turret and before the 2nd near the paths to the jungle but not in the minions' path can turn an almost kill into an easy kill.
Teemo's Noxious Trap can be used to farm creep waves very effectively; it is best to keep your mushrooms spread out and not too close to each other. If a lane has enemy minions stacking on each other (especially the ranged minions), pop a Noxious Trap down in the middle of them and watch them all die in just a few seconds.
Put a Noxious Trap at key locations on the map, such as by the Dragon or Baron Nashor to reveal when your enemies might be attempting to kill them or to prevent opponents from ganking and make counter ganks. This is similar to a Sight Ward but the range that Noxious Trap reveals is much smaller.
Put a Noxious Trap inside brushes and entrances to your lanes or your team's side of the map to ensure maximum safety.
When fighting against a Twisted Fate, be careful because if he uses Destiny everything on the map will be revealed including Noxious Traps.
When laying down Noxious Traps in the jungle, keep in mind that the champion movement pathing often hugs the terrain as they take the shortest route to the selected location. Laying traps against walls at turning points will increase the chance enemies will run into them on their way to/from lanes.
Also, when laying traps in a lane, remember that minions travel through the middle, and if the front minion runs into it only he and one minion behind him will be hit. Placing them on the sides can increase the chances of hitting a champion.
Placing two to three Noxious Traps by the enemy red or blue buff is generally a good idea considering you might just get lucky and steal it from them while slowing their farming down.
If planting mushrooms at Dragon or Baron Nashor, they will provide vision if placed off to the side.
Don't forget that Noxious Trap can be placed down in team fights and only has a short time to arm (1.5 seconds). Doing this could secure a kill or slow down a enemy when he/she is trying to escape.
Keep in mind that Noxious Traps have the damage power of the moment you place them and do not become stronger if you build extra ability power later. They now become stronger upgrades of the skill.
If you are suspecting a possible towerdive from an opposing champion, place Noxious Traps behind and in front of your turret in order to slow and deal damage to the enemy.

I use Flash and Ignite whilst playing Teemo, this is because Flash can be a good way to escape, and it can also be a good way to catch up to people. I use ignite purely for its ability to get first blood fairly easily, or in any case a kill, If they run with fairly low HP I just hit them with ignite wait a few seconds and then claim the kill, it mostly works :)