I have only seen the crackling done on tv. But a thinner paint is not what is required I would think. Try HGTV.com
I think it is in the application of the crackle medium that determines the final crackle paint layer. For example I have heard it said do not go over and over with brush strokes of the medium. How thick or thin the medium is may make a difference in the final paint application cracking.

As previously stated how thick you apply the medium determines how definitive the cracks are. And you can not streak the paint color over more than once. I use a wide brush loaded heavy and make one swipe till the paint runs out, reload and do it again. If you recoat the paint it will not crack through more than one layer of paint. You can do it again if you put the medium down and start over. The drying time of the medium can make a difference as well; each brand usually has it's own recommendation. I usually let it sit a couple hours. Good luck

If your paint in TOO thin, it won't crackle. ~bb