Means to kick things off and get a plan, meeting, or bit of work moving. The idea is once you start, it gathers momentum and everyone can stop faffing and crack on. Not exactly edgy slang, but it’s a solid everyday idiom you’ll hear in offices, pubs, and anywhere people are dodging being first to speak.
"Right, shall we get the ball rolling on this new project? Sweet. Who’s going first then? Everyone stares at their tea like it’s got the answers"