Science is difficult! But it tends to feel easier if we feel supported, welcome and like we belong.
Unless there is a reason to keep a document or piece of code private, let's make it open. So the policy is: open by default. This is partly for strategic reasons - the more we share things privately, the more we have to repeat ourselves, which leads to inefficiency.
Everyone works in a different way. Some people like to work in long chunks into the night, some people like to work a strict 9-5 with an hour for lunch. Work in a way that is efficient for you. And never feel pressured to respond to a message at the weekend or whilst on holiday.