Intern mistakes and how to avoid them?

Hey guys, Serious question, I'll be interning at an MNC in Bangalore over the summer and I got this internship via campus placements.

I wanted to know what are the most common mistakes interns make and what can I do to avoid them?

What technicals should I revise before I start?

My role is a Software Engineering intern.

What do I do to translate the internship into a proper PPO?

Thanks.