First day at a new workplace: what to do and what not to do?

Next week I start working somewhere new, high-tech international company. This will be the first time I see the place where I sit, the people with whom I work at my team and the whole atmosphere around. My bosses I know, they interviewed me.

I thought maybe I should bring something for the first day. Cake? Drinks? I will probably meet everybody, one by one. I will do a comprehensive tour of the building. It is very large and has a lot of things. I come from little start up and suddenly passes to a big high-tech company. It’s a pretty big change for me.

I have slight knees, guilty as charged. I’d love suggestions on what to do my first day job and also what not to do. To my first job I didn’t bring anything, just myself.