During an internship, upholding basic standards of professional decorum is key. So is maintaining boundaries, knowing the right time to ask questions, respecting your superiors and — well, there are a lot of workplace rules that you won't fully learn until you're on the job. 

So before starting that first (or even second) internship this fall, check out this cheat sheet on internship best practices, and heed the expert advice. 

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Curb your criticism:   When starting an internship, give yourself some time to get acclimated before you critique or comment on how business is done. Let's say you're coming in as a social media or web intern, and you weren't impressed with the company's website. "It would be easy to critique the website, but you have nothing to lose by waiting a bit, and you have a lot to lose by spouting your views too quickly," says Allison Cheston, a career advisor based in New York. "Nobody likes a critic, especially an uninformed one." 

Take care of #1:  Some internship programs are well-oiled machines. Others, not so much. "In an ideal setup, your boss would be very forthcoming, and would invite you to have lunch the first day," says Cheston, "but so often, internships are catch-as-catch-can — they're not that well organized." Cheston encourages interns not to expect hand-holding: Ask if you need office supplies, take a lunch even if no one tells you to, and please, use the bathroom.  

Don’t groan about menial work: By their very nature, internships require repetitive tasks. Do the work you’re given graciously — even if it’s boring. “Having an attitude that you are learning simply by being in an office environment and seeing how work is done will help you frame these types of [menial] tasks — and being good-natured about executing them will go a long way toward impressing your bosses,” says Cheston. Truth: Nobody starts at the top.

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Know when to observe : An internship is a learning opportunity, and sometimes, that means your main objective "is to relieve your boss of work stress while making her look good,” says Cheston. “The early days of an internship should be devoted to watching and listening and completing work in an organized, intelligent fashion.”

And when to step up:   That being said, if you're not getting anything substantive out of the internship, then that's an issue. Never   accept only rote tasks during an internship, says   Heather Huhman, a Gen Y career expert and the founder of the PR firm Come Recommended. “If you're being given only menial tasks, come up with a list of 3-5 tasks you would like to work on that would also greatly help the company, and request a meeting with your boss to discuss them,” she says.

Ask questions:   Bosses don’t always have time to explain everything in detail, but you should show a sense of curiosity about the work. But be careful — that doesn’t mean pinging your boss with every minor concern. Says Cheston, “If you ask questions that you should be able to find answers to on your own, you are wasting her time and adding to her workload. There's nothing more annoying than having a young person constantly expecting to be given work to do, and needing a lot of guidance."

Make the most of it:   If your internship is an unfulfilling disappointment, just look at the bright side: Now you know what a real job is like. Just kidding! The reality of internships is that "many times you'll be frustrated, and your expectations will not be met," says Cheston. However, don't underestimate the power of persistence. "Even if you think you're not learning, you are."