Now the object is to save your fleet by putting them on what? Mission or trading thing. But how does this work? And if I'm gone for more than 12 hours? I realize that Moon to Moon missions are the safest, but from my experience I don't see them lasting more than how long I need them to. In general, I guess I don't get the fleetsaving idea. Could anyone please explain it in a more direct way? I understand the goal. But what should I do to be successful at it?
I need to protect my small fleet

tl;dr no idea on fleetsaving.