冖 is a pictograph of a cover or cloth draped over something, representing the idea of covering. It is used as a radical in characters related to covering or enclosing.
Meaning mnemonic
冖 looks like a lid or a cloth placed over something, like a crown covering the top. Think of it as a cover radical.
Reading mnemonic
For ベキ, imagine a crown that makes a 'beki' sound when placed on a head: beki -> ベキ, like a soft thud of a cover.
