[ManuelHeL]

One key aspect is a single source of truth. A place/tool were all processes, requirements and relevant Q&A are open for the whole team, with no gray areas. Use any kind of methodology, but try to keep your team informed about how the general rules of communication and collaboration work.

Split communication in small teams/groups and design just one person per group to deliver periodic status. Meeting with the whole team are absolutely inefficient and costly for the company.

Create a policy where any change must be documented and informed to all stakeholders.

Tools vary depending on your business, but sites like Trello can be really usefull.