Quick answers
What is quick cast and should I use it?
Quick cast fires an ability at the cursor the moment you press its key, skipping the targeting circle. Almost every experienced player uses it (Options › Hotkeys › Quick Cast All), with Quick Cast with Indicator as a middle ground.
How do I attack-move?
Press A and click the ground; your champion walks and attacks the first enemy in range. Set Player Attack Move Click in Hotkeys to do it with one key.
How do I level up abilities faster?
Hold Ctrl and press Q, W, E or R. Many players swap this to Left Shift or bind Level Up to keys near the ability row.
How do I ping missing enemies?
Hold G and drag toward Enemy Missing, or use V for the retreat ping. Pings on the minimap work the same way.
Can you play League with a controller?
Not officially; the PC client has no controller support. Wild Rift on mobile uses touch controls instead.
How do I turn on spell buffering in League of Legends?
Hotkeys › Casting Modes › Cast the pressed spell upon pressing another spell. With it off, a combo pressed faster than the game accepts simply throws the second key away.
Should attack move be on cursor in League of Legends?
Yes. Game › Gameplay › Attack move on cursor makes A resolve where you are pointing rather than at whatever is nearest your champion — the difference between last-hitting the minion you chose and the one the game chose.