From a tools/infrastructure support perspective, standardizing on tools and clearly declaring and assigning a single tool for each function. Clearly ask people to pitch in to adhere to this. Set clear standards for yourselves.
From a people perspective, clearly defining goals and constantly asking clarity questions to gauge if there is alignment is the only real way. Also if you notice people are not aligned but they think they are, declare that you're not sure they're aligned. They'll hash it out themselves.
It also helps for people to declare when they're unavailable in something like a slack channel. Finding out someone is not there when you expect the to be is very jarring/frustrating.