Get your pan full. Get your hand in there and mix it all up. This is so you can get ALL of the material wet. Then, shake the crap out of it. Side to side. How long it takes to stratify depends on your pan and how you shake it. I get 6-8 side to side shakes, and everything is good and stratified.
Now, drain the water off. You should see pretty much all the stones sitting on the top. Now, fill it up with water again. Then, while tipping the pan slightly, shake the water off of it. You should see material Running off the end of the pan with the water. Those are the stones. Remember, the whole time, you are shaking the pan side to side.
Now, fill it back up with water, give it a few more side to side shakes while keeping the same angle, but not lettting water run off it. This re-stratifies your material again. It also is driving the heavies down,down,down into the pan.
Now, fill it with water, and steepen the angle. SHake it and let the water run off with more stones. Keep repeating this process until you have a small pan of material. ( What I like to do at this point, is to wash this material off into a second pan. That way, I can get 3 or 4 pans of material at the same time. It is a huge time saver, and the visual effects of seeing 3 or 4 pans of black sands and gold at the same time is a lot more fun as well.)
When you have only a cup or so of material in the pan, lessen the angle of the pan, fill it with water, and shake it again. And again. Let most of the water run off. Now, reverse the angle while you are shaking the pan lightly. This should wash the lightest material to the back of the pan. Keep shaking the pan lightly and the black sands should walk back as well. Your gold will be on the leading edges of the black sand at this point.
A couple of tips. First off, you have to be continually shaking the pan. The entire time. When you are picking up the pan out of the water, you are shaking it. As the stones wash off, you are shaking it. You should have water splashing over the sides of the pan! If your tub is full, water will be splashing over the sides of it as well.
Next tip, you don't need the fanciest pan on the planet. I literally started out with a Marie Callenders pie tin. I don't feel handicapped with it to this day. The only problem is that it is small. But, if I am in the desert, and am pannning my concentrates in a 5 gallon bucket, it works great.