Barton got it right. What you are actually doing is tapping the area by moving the wrist back and forth, causing the cane to repeatly strike the target area. The intensity of feeling this produces for the sub is based on the size of the cane (thinner versus thicker) and the force with which you are striking.
Does this produce bruises and marks? Yes, but it all depends on the intensity of the strikes. What is produced at first is a redness of the skin, and if you listen to my subbie tell you, the most delicious sensations that course through out her body. I usually work with one size cane (from smaller to bigger) for quite awhile. (of course this depends on our overall time allowed). Then I switch to the next size cane and work the areas over again. You can also use two at once. I usually develop a rhythmic tapping with the smaller one and then do random strikes with the bigger one. The best areas of the body that create the best feelings are the buttocks and thighs. You don't have to have alot of flesh down there for this to be effective, but if your subbie is very skinny and doesn't have much ass, you need to vary the intensity and time of the session.
The key, as with all D/s things, is to try it and talk about it. Also, I always talk to her throughout all sessions. Now, we have been together going on 5 years, so I know how she reacts and can read her body and know what her noises mean. But if you and your subbie or Dom, are just starting out you need to go slow and then talk. Also, if you are trying Tattoo caning for the first time, start with the smaller canes first and maybe only do one or two sizes, avoiding the larger ones till next time.
A neat little trick you can do with canes. After being warmed up (the subbie that is), take the thickest cane and put it between her legs, so the shaft of the cane is right in between her vaginal lips. Then strike this cane with another one. This causes wonderful vibrations that course through out her body. I know it is hard to describe all of this with just words, so if you get confused either post here or PM me and I'll try to work through it with you.

I have been talking about Male Dom and female subs, but obviously this could work with a male sub, though I have not done it on one. I also don't know the effect of caning on the scrotum or cock itself. Guess I will have to go find a subject to experiment on. Ha, Ha, Ha.
You can tattoo cane the breasts, but thinnest cane only and very light strikes (tapping), usually the under part. Also this works better on women with more tissue than less. Mainly you wish to avoid any areas that are muscles or nerve areas (like the shoulders, spine, as well as kidneys, etc.).

Hopefully I have made you curious that you and your partner wish to try it. I was very wary when we first started this. Mostly because I have always viewed canes as a painful deliverer of intense blows. But everything can have a softer side. We now do tattoo caning almost all sessions, at least to some degree.

Let me know if you have more questions. Also, I will try to get my subbie to post and tell you her side of it.

Take care, be careful and enjoy!


SirW