The 29 best people in advertising to follow on Instagram Lara O'Reilly Advertising Jun. 17, 2016, 12:13 AM 12. Sheryl Sandberg, COO at Facebook. WHY? An inside look at what it’s like being the most powerful woman at Facebook. Share Tagged In advertisingAppleFacebookGoogleHow ToInstagramPowerfulTechthelife Discuss Comments are closed.