Knock your boots off

Relax, have some fun,… knock your boots off!

Overheard in Alexandra Palace, London, UK.

A mixed idiom made up from

1. Fill your boots,
2. Blow your socks off, and
3. Knock yourself out.

Context

Used in the context of encouragement to have fun, to relax, to be less straight-laced, and to enjoy oneself.

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