Communications are radiated when events happen, so teammates can be in the loop.
Communications provide equitable participation for everyone involved.
Communications use relevant channels, such as chat, or email, or video, or wiki.
Communications records should be readable, searchable, commentable, correctable, and linkable.
Communications are mutual interactions, and use mutual respect and mutual purpose.
Communications aim to help "maker's schedule, manager's schedule".
Over-communicate. It's usually better to say too much and too often, than too little and too seldom.
For communications in meetings, try ways of working for meetings.
For communications in our group get-togethers and our video calls, try ways of working for signing.
Teammates commit to read communications sent directly to them within 1 business day of receipt.
Teammates commit to response times for various channels (e.g. chat, email, phone), various purposes (e.g. questions, reviews, invitations), and various notations (e.g. a message that says "Urgent" needs a response immediately upon receipt, or a message that says "FYI" doesn't need a response).
Enable read receipts by default.
Communication expectations should enable your team is working across time zones
Ensure social networking is up to date, such as for any employee directory, organizational chart, company website, LinkedIn page, Twitter feed, etc.
For more-formal teams, establish a service level agreement (SLA) on communications. This means writing expectations that can be shared with the team and also with other people who interact with the team in meaningful ways. Ensure a leader is responsibile for the SLA and its ongoing use.