Will Get a Wriggle on?

to hurry up: I haven't done my birth plan yet, so I'd better get a wriggle on.

Is it get a wriggle or wiggle on?

This expression is used when you want to tell someone (quite forcefully) to do something faster. In the UK get a wriggle on is more common. In the US get a wiggle on is used more.

Is there a word wriggle?

verb (used without object), wrig·gled, wrig·gling. to twist to and fro; writhe; squirm. to move along by twisting and turning the body, as a worm or snake.