When I joined Aviva, work on their agent portal had begun. The team was struggling with the designs produced by an external agency for the public website. The agent website had much more content and planned functionality so new layouts and UI patterns were needed.
I worked with Business Analysts who were writing business requirements for each area of the site, creating wireframes to accompany their documentation. Once approved, I would design new UI elements and I work with developers to implement the design. If technical issues came up, we would whiteboard out options to come up with a design solution that would work. I did quite a bit of CSS tweaking to get the design of elements just right. I participated in daily standup meetings, show and tells, user acceptance testing and usability testing sessions.