Make no mistake—you’re going to make mistakes along the way. That’s perfectly okay. That’s what being an intern is about. You’re learning; people expect you to screw things up now and again. No sweat. But honest mistakes coming from a hardworking intern are one thing; the following mistakes are ones you simply cannot afford to make.
Act like you’re above lowly tasks. As an intern, you’re going to have to do a lot of boring, lowly tasks. You’re not going to get the exciting projects right out of the gate. Your boss wants to see that you are dependable and have a good work ethic before he or she will hand you more interesting work.
Dress unprofessionally. Dress for the job you want to have, not the job you have. If you come in dressed like a casual student, no one will take you seriously. Pay attention to how the true professionals in the office dress and try to mirror that in your own dress.
Talk bad about others in the office. No one likes the office gossip, especially when he or she is an intern. Keep your mouth shut, and respect everyone around you. Not to be too harsh, but you’re the lowest person on the totem pole, and you’ll never gain respect by talking bad about others in the office.