How to approach a marital seperation - (Part 1 of 2)

Can you provide some guidance on how to navigate a marital separation? Our marriage has been plagued by conflict and emotional pain for a long, long time. As a result, we've come to the conclusion - sadly and reluctantly - that we need to get away from each other for a while. I honestly don't know if our relationship is going to survive, but for the sake of our kids and our own sanity I want to go about this process in the best way possible. Who should we tell? How should the two of us interact while separated? How do we handle finances and other practical matters? What other issues do we need to consider?