I work with a team of people scattered across the country. We've mostly communicated with Slack in the past but needed something to help track our projects. We've set up a team board in Trello, each of us has our own personal to-do boards and we've installed the Slack app to get notifications. At first, every time somebody posted something on the team board everybody would get notified even though most of the time, tasks just need to be viewed by one or two people on the team. We went in and adjusted some of the board/card settings but we're not getting the results we'd like. So I'd like suggestions about the best way to put items on to the board that will only notify those individuals that need to work on that task. Here's what our board looks like now.

Thanks in advance for any advice!