A day in the life varies greatly by what team you're placed on and how involved your managers are. You will likely attend many meetings and help take notes for your manager. Additionally, you will start to take on small day-to-day account managements tasks. You will likely be assigned a final project that you also work on throughout your 10 week internship, and towards the end of the internship, you will begin working in teams on an intern-wide assignment.
On a typical day, you are assigned tasks such as organizing and creating draft sheets for deliverables, or in and out of meetings with clients & working on your internship project! You learn a lot about the communication between the client and the decisions made. There's a lot of working parts and you will see that when strategy,account, and other departments come together.