I know this is going to sounds obvious or simplistic, but it helps me when I have complicated situations that seem overwhelming to break them down into lists of concrete steps I can take, and just start doing things one at a time. Sometimes, in making the lists, I discover things that actually do not require action on my part at all. It just helps clear the clutter out of my head. I have been known to wake up in the middle of the night worrying about something, and getting my phone out while I'm lying there to make a list.