When I started out in business, I was much younger than most of my colleagues. Rather than take advantage of that by playing it up, asking for help, and thus developing life-long mentors, I just pretended like I knew everything and then worked my a$$ off trying to figure it out. This strategy was flawed for a number of reasons that you can guess, including the fact that I wasted tons of time in my twenties at work, when I should have been having adventures and discovering new hobbies and drinking beer. So that you, Fair Reader, don't make the same mistake, here are some suggestions:
Let your personality show. I was so nervous about being taken seriously that I acted like a 60-year-old British librarian with a back brace in my first interview. I even wore my hair in a bun. I later found out that I almost didn't get the job because the woman interviewing me thought I wouldn't fit in with the light-hearted team. Trust me: no one is fooled into thinking that you are older and more experienced than you are. When you are young, you're getting hired because you are enthusiastic, smart, and cheap -- not because your employer thinks you're the most seasoned candidate. Go with it.
Correct trumps creative. When it comes to the dress code, that is. So many younger women are fooled by chick lit and Glamour into thinking that their weekend wardrobes can be mixed in with business attire to create funky new looks. Seriously, you are not skilled enough to pull this off. It is much better to have five boring neutral suits that you wear every day and know that you're OK than it is to try to mix it up and cross your fingers. My favorite example of this was Billie, who worked for me when she was about 23. A selection of her ensembles included: a wrinkled, Oxford-cloth shirt tucked in (tucked IN!) to the bodice of a strapless dress; a satin, red and green plaid ball skirt (which touched the floor!) with a black suit jacket; fuzzy purple knock-off Uggs with a knee-length skirt; and a black leather cheerleader-esque pleated (I know!) skirt. Horrific. Please note, you should totally push the envelope when you are a little more established; just don't do it before anyone can tell if you have a clue or not.
Don't leave last. It's kind of embarrassing to admit, but everyone loves those early work happy hours when you're getting to know your boss and co-workers. You look forward to them when you're young because there's a good chance your boss will both pay for your drinks and spill some juicy gossip. I am a big believer in bonding over booze, but don't let yourself be the last one to leave. No matter what. Even if you are having SO MUCH FUN!!! and bonding with everyone or even falling in love. Be among the first third of the departures. This ensures that you get the points and cred for being there without any of the scandal and humiliation of being there too long (or leaving with the other last person there - ewww).