I liked that it kept my mind sharp all summer. I was immersed into a real life agency and had responsibilities mainly revolving around content writing for websites.
What I wish was different
I wish I could have done more group work with the other interns. I think a lot of "real-life" working, especially in this field, is done together and I didn't experience this.
Advice
Working hard, getting your stuff done and staying focused pays off. My boss asked me to continue to work for them paid this school year after a summer of unpaid work because he liked what I was doing. Staying on top of things and giving good quality work pays off even with unpaid internships!