"Pro-Tips" for Beginner League of Legends Players?

Inspired by one of the times I played on the Garena server.

Someone on the enemy team must have been brand spankin' new to the game because they not only asked for advice on how to build Kha'Zix in the /all chat, but they also followed what I suggested to them. I told them "You're building him wrong. He's all AP. Kappa." Lo and behold, he's rolling up to my lane with a blasting wand and a tome.

I only felt a little bad.

So what believable "pro-tips" would you guys give to someone new with the intent of messing with their innocent and trusting selves? For example:

• Did you know: Riot secretly implemented a feature to help players who are new to their champions succeed even if they aren't building the right items? Building ability power on a primarily AD champion, or vice versa, unlocks a hidden buff that will convert your champion's damage scalings to match the type of damage you're building. This effect, however, only applies after building a third item of single type damage. For example, building Guinsoo's as your third item after building Bloodthirster and Infinity Edge would not grant you the buff because Guinsoo's gives both AD and AP.