Breaking into an existing group, in whatever form (sports team, social clique, company, or consulting project team) can be a daunting task.
What is the NUMBER ONE tip?
Cliche, but being nice to others makes it easier for them to be nice to you.
So be very polite and nice, say hi to almost everyone. Introduce yourself, ask people polite questions about what they do and show an interest (your making them a friend/ally, and it helps you figure out who does what; you might even learn about office politics).
Learn the jargon and use it. If nothing else, you give the appearance of being an insider who knows what is going on. Done properly, this works well. If you use the language incorrectly, you look rather foolish (kind of like how Americans think Canadians and the British are "quaint" for the unique words they use like "water closet" and "telie"; secretly this is why "Harry Potter" was so successful, the accents). Jargon is important. And beyond implying you know what you are doing, it is a cue to those around you that you belong, you have a handle on the situation, and you understand the work being done. On my newest project I didn't know what a "walkerbox" was. This was a very basic term, and made me look bad to not know.
Offer a helping hand. This is helpful and endearing to your new teammates, and to you. For you it is worthwhile because you can quickly, make connections, and pick up on a lot of the cultural elements. You can help your teammates by offering them assistance with even menial tasks, demonstrate you're a team player, and help them advance what they are working on. "Learn by doing" right? Well here's how to do, learn, and have it all be in a low risk environment. Often times people won't even take you up on the offer, but you at least made it (and should do so in an authentic way). Those who do take the help, will typically give you less than critical tasks. Which is great. Semi-trivial tasks still fit into the overall flow of work. You can see what feeds into your little piece, and what relies on it.
Work hard. Put in an honest days work. Show an interest in what needs to be done. Let them know from day one that you are there to help out, and you aren't more dead weight.
Show an interest. Ask questions and be inquisitive. Ask for documents to read, background material, examples to learn from, templates to use, etc.
Help the next person. Take notes, write down what was helpful to you. If there is formal "new person" or "on-boarding" materials then discover what gaps there might be. If there is no guide, start creating an informal to help out.
What other tips or tricks might people have?