Come in with an open mind and willing to work. Really, it's that simple. If you continuously (though not annoyingly) ask your superiors for more work, they will appreciate you. Also, be willing to do the things that they don't want to do. There are some pretty boring tasks that need to be done, that they will be very appreciative of you doing.
After my internship with EY, I believe the most important thing is to keep asking questions. There is high chance that you will run into something out of your expertise. Other team members are always willing to help you, but you have to let them know. Curiosity is also an essential trait you need to demonstrate. First, you will probably enjoy the work more if you understand what you are doing and why you are doing it. Secondly, asking smart questions shows your enthusiasm for the job. Lastly, because of the nature of the assurance practice, you will need meticulousness in everything you do. The ability to notice a mistake either in doing a review or examining client’s paperwork is significant. Also, as you will be working with Excel a lot, it is necessary to keep the data precise.
To succeed at EY, the most important attributes one can have is communication and person-ability. All of the work we do for our clients is team oriented so being able to communicate effectively with your teams and ask questions when necessary is extremely important and goes a long way. The work is complicated but there aren’t any expectations so there is nothing to fear there. Just having a good head on your shoulders and a positive attitude is something I would focus on, and your team member will teach you the rest.
The most important thing you need to be successful at EY is really to be a good listener and a quick learner. The senior members on the team you are working on will constantly give you new tasks. They will show you exactly what you need to do. The key is to take notes and try to learn about all of these different tasks.