100. Karthus.

If you are first pick, communicate with last pick in champ select. Offer to trade for their champ.

Don't play on a Nokia N-Gage

Don't assume only supports need to buy wards

Don't push lanes past the river alone.

Never start baron if they're all missing and also stronger than you.

If you lost the majority of your towers and they have map control, start warding your own jungle and objectives.

If you see you have a clear disadvantage against another champion, play safe, meaning you can't get in range of him, only go in to last hit, and if that's not possible, play passive until you get a gank but make sure to ask for one too..cause some junglers "forget" to gank.

Play a champion until you know who he does good against and who does good against him.

If a player dies twice in a row..go gank that lane...immediately, and preferebly twice..to give your lane a chance to comeback.

If you have a squishy team, make sure to pick/have at least 1 tank, and preferibly with cc.

Everyone must ward. Top and mid included.

If both teams are of equal strength, ward their blue/red for possible ambushes you may do.

Don't try new builds/roles in ranked unless you tried it before on normals and it worked. (not trying once, but several times)

Can't think of anymore at the moment.

A good excersice is to check the minimap every time you last hit a minion. Do not stand watching the gold annimation popping out as it is irrelevant. If you succesfully last hitted him, you'll get the gold anyway. Do not waste that fraction of time!

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Ban Teemo

Don't have a set build, adjust and adapt to what you need against their team or to help yours. Even if that means awkward item builds.

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