One, be as transparent as possible, as early as possible. Hopefully your company has not been hiding that there are financial problems so that it won't come as a huge surprise that layoffs are happening. If you haven't done this yet, please start communicating. You do not necessarily need to tell the whole company that layoffs are happening, but you do need to tell them that this might happen.

Two, avoid saying anything about how hard this was for you. They do not care.

It is definitely best to tell people in person, and individually. I don't have any advice as to how to do so in a small space. It is for the best to restrict access to sensitive systems once a person is laid off, but you can keep them access to slack or email so people can say goodbye if they'd like.