Ligaments are a big one for me. A lot of people seem to have a hard time with that one. When they feel the hind end getting mushy they miss the fact that the ligs are still actually there. If you can get good at knowing when the ligs are actually gone (as opposed to just mushy or hanging low, which can be the case for days before delivery), you'll be much better able to tell when they're actually eminent. The hard ones are the ones whose ligaments don't disappear until they're almost in labor. They give a false sense that they still have a few days to go and then, whoops! There's a kid! Another one that works pretty well in my situation is separation. Now, some does will separate for several days before they go into labor, and a very few won't separate at all, but most of my girls stay with the herd and then separate themselves a few hours before delivering. Many people separate their eminent does from the herd which eliminates this "tell." You also have to keep a close watch on your herd throughout the day or you'll miss the sign. I have to be careful because my girls often like to sneak off into the scrub oak instead of going into the clean, comfortable sheds I prepare for them. All that work, and they'd rather have babies in some nasty, God-forsaken, rocky, thorny, root-covered patch that I have to crawl on my hands and knees to get to!