Make sure you dont die early game , and poke the enemy champ as much as possible. that makes him not get alot of cs letting you own your lane alot more and get yourself more cs. make sure you get good cs because the faster you get lichbane the better you can poke. your shrooms should be placed mostly in the river, in the bushes and along the path where the minions walk along but dont put it where they can step on them. in the river is very important because its the most effective way to stop the enemy champion from ganking you(can't tell you how many times i got double kill when they try to gank me and my shroom slows them so i can burst them so easy.

Ps if you're fed always roam to other lanes especialy bot because your blind can easly stop enemy adc from attacking and so help your adc get some easy kills.

Pss in team fight always target the champion who uses basic attack the most (ashe,udyr,twitch,jinx and so on) and then target the ap caster because they usely have low hp

- Loyal Teemo friend