get the ball rolling
US /ɡɛt ðə bɔl ˈroʊlɪŋ/
UK /ɡɛt ðə bɔl ˈroʊlɪŋ/

1.
to start an activity or process
:
•
Let's get the ball rolling on this project.
•
We need to get the ball rolling if we want to finish on time.
to start an activity or process