fall over oneself

fall over (oneself)

To expend an inordinate amount of energy or effort to do something, especially as a means of gaining attention or approval. John is such a teacher's pet, falling over himself to impress Mrs. Smith. My parents fell over themselves trying to seem cool to my friends. It was pretty embarrassing, to be honest.
See also: fall, over
Farlex Dictionary of Idioms.

fall (all) over oneself (to do something)

Fig. to rush eagerly and awkwardly to do something. The boys fell all over themselves to open the door for Sarah. Larry fell over himself trying to help Sarah on with her coat.
See also: fall, over
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • fall over (oneself) to (do something)
  • fall over yourself
  • fall over yourself to do something
  • fall all over (oneself)
  • fall all over oneself
  • expend
  • fall over backward
  • fall over backwards
  • expend (something) for (something)
  • expend for