The best process I've seen is the one I myself went through when
joining P&G (quite a few years ago now ...!) Since then I
worked for many years as an external consultant, and was able to be
accepted as "one of us" by every team I worked with, usually by the
first day I started. In fact, people were usually shocked when they
were later reminded I was actually an outsider and was going to
leave soon, in spite of having been told my temporary status openly
right up front.
Here's a generalised version of the best etiquette to use to integrate yoruself:-
0. This is actually an additional point: it's a good idea to make friends with the receptionist, even as you arrive. She (or he) carries a very important function introducing you to callers, and many people will go to her to size up anyone they don't know in the company. If you tell her who you are, who you will be working for, and what you will be doing, she will immediately begin to smoothe your arrival behind the scenes.
1. This is where you start in earnest: Meet your Boss, and take notes of what he (or she) says. Especially note the precise words he uses to state your goals and your title. It is important to get the words right, since every company has its own unique language and you want to begin sounding like an insider as soon as possible. Also, he will notice you doing it and will give you credit for fitting in quickly.
1a. If you've not already done it, you may go to HR to complete any paperwork that's necessary. Of course, you will have met them already, but a formal "welcome to the team" is important. In some companies they may want to give you some additional directions about how to fit in.
2. Go to your workstation, leave something personal at your desk, and take a notebook. At this point you've "arrived".
3. Look around your workstation and introduce yourself to the people you see there.
3a. If you are going to be the manager responsible for a large team it might be appropriate for you to call a team meeting at this point - so they can see your face and hear you say a few words about yourself. If they ask questions you can either handle them immediately, or (more likely) thank the questionner and say that you'd like to come back to them with a proper answer in a few days' time after you've got fully familiar with the situation.
4. Next, find out the names of everyone in your work team, and meet them individually, 1:1. A suggested agenda for these 1:1 meetings is included below.
5. Then meet your boss' peers - other managers, who's opinion matters to your boss and to your own career.
6. Then seek out the heads of other departments and introduce yourself to them.
By this time you'll probably have met pretty much everyone, and a very useful final step is to:-
7. Meet with the top manager of the company - the MD / GM / CEO / Site Manager / etc. - you may well be introduced briefly on your first day, but actually is best done again after you've met everyone else. This gives you an opportunity to show what you've learned, and demonstrate that you are taking personal responsibility for making sure you align your work with his vision and leadership. It may only take a few minutes, or be a more formal process lasting 1/2 hour, but is worth doing.
The other related question is what to do as you meet each person, and here's a suggested agenda:-
a) find out the person's name, title, functional role, and contact from others first.
b) call them, introduce yourself, and suggest a short meeting to get to know each other, and agree the time
c) when you meet, introduce yourselves to each other. Here's a checklist of points to inclued:-
name, title, who is your boss, what is your mission -
then a bit about your past experience, how you came to join the company, and what your ambitions are -
then spend some time discussing the company - what's good about it and what are the goals for the year, in particular how each of you plans to make a difference.
Who goes first in the conversation depends a lot on the personality of the person you're meeting - some people will want to talk about themselves first, others will want you to spill the beans first. Some may want you to be crisper and more formal, others may appreciate a more casual style that nonetheless covers all the important points.
Finish up each meeting by discussing mutual expectations - start by asking "is there anything you specifically expect from me in my role?" and then go on with your own expectations, if it is appropriate in your relative status.
Of course the precise path you follow should be tailored to your circumstances and the culture of the company - your boss will probably give you guidance about what is expected - but if you are allowed to do the steps in the order above you will very likely experience a smoother integration than if you do something different.
This is pretty much the same regardless of whether you are a full-time employee, a part time contract employee, or an external consultant. People are people, and the social rules that govern whether they trust you or not are pretty much the same everywhere. Always remember, you are the outsider, even if you are coming in to take over a leadership role, and "you catch flies faster with honey than with vinegar".