Once you’ve been the new kid, you never look at the new kid the same way. Go sit with them.

Having been the one standing with a tray and nowhere obvious to go gives you information most people in the room do not have. You know that the new person is not quiet or stuck up, just working out where to put themselves. That knowledge only converts into anything if you act on it fairly quickly.

When somebody new turns up, be the one who speaks first and does the dull practical thing. Show them where something is, ask what they did before, make space at the table. It takes a minute and they will remember it for years.