defo keep me in the loop

A phrase used to indicate, "Not a chance."

"George! Would you like to go see a Marvel Cinematic Universe marathon?"
"Defo keep me in the loop!"

Keep the Heid

A more Scottish way of saying "keep the head"; it means to stay calm and keep your mind away from going crazy-loco or angry.

"Look, it's no even worth it. Keep the heid!"

The cake keeps on layering

Similar to "layers to an Onion" or most importantly "the plot thickens",

It means that there is information (significant or not) that wasn't revealed until recently

Oh? the massive event has more information on it, "the cake keeps on layering"