This is my 4th year digging. My cousin is getting older, and wanted to pass her knowledge on to someone, and I was eager to learn. I can share with you some of the things that have helped me find it.
If the berries are still on, it's great because it is so easy to spot. But don't count on that, you need to learn the leaf and have it imprinted in your mind so much that you can spot a plant from 20 paces away.
Pictures are good to give you an idea, but to see one up close and study it is really helpful. The leaves are very distinct once you really look at them compared to other plants. The edges are saw-tooth, but not too big, just a little bit. I can't say I've found a small ground plant that has a leaf edge exactly like ginseng.
The main stem grows up and splits into 3 or 4 prongs, all from the same point, and also the crown grows from that same point. Not many other plants even have a crown. It really is the give-away. I've found plants before that had lost all their prongs, just a stem with a crown. And not many other plants branch out from all the same place on the stem.
Each prong has 5 leaves, 1 big, 2 medium, and 2 small. Each leaf gets wider as it grows out (opposite of many other plant leaves), and then at the very end it forms a curved point. I know you can see this in pictures, but you may tend to overlook these subtle traits unless they are pointed out.
The color of a ginseng leaf is hard to explain. Pictures do not do it justice. The green of a ginseng plant is different than any other plant, sometimes you can spot a plant just based on it's color alone. It's not waxy, more of a flat green. It is very vibrant, more bright than the other plants. Sometimes they have a slight speckle coloring on them. It is really hard to explain, once you see a lot of them you will understand.
Look close to the ground. In my area, even a plant with a 12\" stem, is not actually 12\" off the ground. Usually they are lazy and lean over and the top is nearly resting on the ground. Many times I've found them underneath ferns or other plants.
I hope this helps.