Hold on to your britches

Meaning

A way to tell someone to get ready for a big change, an exciting event, or some shocking news. It implies that the situation will be intense enough to knock you over.

Playful, anticipatory

Used in a sentence

• Hold on to your britches because this prize is going to be huge.
• The roller coaster is about to drop, so hold on to your britches!
• Hold on to your britches, I have some news that is going to change everything.