Admitted Students days can be exhausting but informative, in the best case scenario. In all of my experiences, I attended these hosted visit days after already accepting my admission; however, many students go hoping to find another tidbit of information that can help them with a difficult decision. Regardless which camp you fall in, you should find this information useful.
Prep work. Since you've already applied to the school, you're likely pretty familiar with their program. But as you consider actually going there, you may have more nitty gritty questions related to funding, coursework, or general program structure. These are the hard pieces of information you should use to compare and contrast different schools. Next, think about your past educational experiences. Do you do better in large lectures with separate teaching sections, or in small group discussion classes? Do you utilize office hours like it's your job or do you prefer study groups with colleagues?
Last night, I flew back north after a whirlwind trip for Admitted Students Day. Since I've already accepted the admission offer, my focus for this trip was to hash out my expectations for the upcoming year and to leave a memorable impression on my future advisors and mentors.
Reflecting during the plane ride, I realized that the approach I took during my meetings and interactions could be articulated for you to address the issues of imposter syndrome we all struggle with at one time or another.
Setting the stage. The first step is to create your context. You need to establish your overall goal so that you have a solid "big picture" to come back to during hard times.
"The best productivity hack is blocking the time to do the work that produces the results you want from your life, a big part of that life being your work, and work being one of the ways you make a contribution." [source]