This is something I will soon be trying for the first time. After browsing the 5 screens of archives in this forum, I noticed there has been a good amount of commentary going back 3 to 4 years now, but not a lot in the way of formal instructions. I've seen where various people refer to "it" , as in, an article that they read or alluded to but did not excerpt or directly quote into the forum, but instead just indirectly referred to it. This seems like a good reason to post a current post that contains some actual step by step instructions. This is not meant to be an end-all be-all guide on the topic, but a basic "how to?". Others are welcomed to add their own tips & experiences of what works.  The best I've found so far from the archives come from this post:

http://curezone.com/forums/fm.asp?i=801213#i

The above instructions are said to have come from an Edgar Cayce reading. These instructions seem fairly straighforward and also seem fairly thorough.

The below information was taken from a hard copy of the John R. Christopher book - School of Natural Healing. He provides some valuable information that I did not find (at least, not yet) in reading the Cayce reading.

The first note of relevance from Doc John's information is that his procedure is found within the section of the book that provides in-depth instructions for his overall "Cleansing Program", of which the Castor Oil pack is just one among several procedures to be used in restoring one's health. This section of the book constitutes 30 pages, and includes instructions on several of what Doc called "corrective aids", to include the 3-day Cleanse, Mucusless Diet, extended cleanses using various herbs, and herbal combinations to be found (then) on the market.

The Castor Oil Fomentation is the first procedure listed under Corrective Aids; " in order to get rid of hardened mucus in the body, which may appear as cysts, tumors or polyps....". The operative word here is "may". In other words, in Doc John's view, this fomenation "pack" can be used for many many different reasons and conditions that a person is attempting to correct, cysts, tumors and polyps appearing internally or externally among them. To further clarify this, he said  " this castor oil fomenation is excellent for any ailment where the liver is congested - and that can be with most of our illnesses"  

Doc John advised the castor oil pack be placed over the entire front torso "from neck to groin and side to side". Compare this to Cayce's instructions that focuses the pack directly above the liver as well as just below (the right rib cage) as well as just above (IE> on the right rib cage). There generally are few hard & fast rules when it comes to the scope of natural treatments here. In the case of Castor Oil packs, the individual should be glad that they have a range of options for using it, either specifically over the area of the liver or over the greater area of the upper torso, which either method can be used to produce health benefits.

Doc John advises the use of "outing flannel" or baby's diaper. Try to keep in mind the era he worked in. In other words, he likely did not have greed-motivated multi-national big-time corporate factory-produced "pampers" in mind, but instead meant real diapers made out of simple, natural material - like plain cotton. The archive has several examples of people asking "why flannel?". Being familiar with various works of Doc John, I know that whenever he uses a material that will be placed in direct contact with the body, he advises the use of "real, natural material, like cotton, flannel, wool or silk....natural fibers that breathe". Additionally, it seems likely that natural materials will be less prone to introducing new problems into one's desire to effect corrective aids, as opposed to un-natural, synthetic materials, that may hinder these efforts due to introduction - potentially, of harmful synthetic components that leach into the body and cause more harm than good. I was not familar with the term "outing" as it applies to flannel, and looked up a definition. The term seems to be referring to cotton material that is plain, white cotton with a bit of nap "downy texture" woven into both sides. I imagine this can become more of an expsense consideration  if one intends to use the Castor pack over the entire torso as Doc advises. Alternatively, covering the area of just the liver significantly reduces how much cotton/flannel and oil material one needs to acquire.  

Soak the natural material in castor oil, then wring/squeeze slightly so the material is not so soaked that it will easily drip oil all over the place. Place the oiled material directly (and flat) onto the skin of the body - either the area near the liver, or over the entire torso as mentioned above.

Given the need to acquire the material for this procedure, it is worth pointing out that the same piece of castor oil soaked material can be used over and over again if it is properly taken care of in between uses. This is not info that is provided by Doc John, but moreso general purpose info that I've picked up from reading here and there, including the Cacye info. After a given application of the fomentation, the piece of oiled cotton/flannel material should be stored in an air-tight jar or plastic bag. Each time it is re-used, give it the old "nose test" to see if it has a rancid odor. If it does, it's time to discard and replace with a freshly oiled piece of new cotton. The Cayce info indicates that if properly cared for,  the same piece of oiled flannel can be used for up to a year. From one person to the next, there no doubt will be variations involved, so be sure to be on the lookout to observe and or smell when it is time to discard the flannel.

Doc John does state that this castor oil fomentation will "absorb through the skin and into the liver and lymp, drawing out toxins and helping to flush them out of the body". Since he does not state it outright, it is easy for somebody to assume that all of the toxins drawn out of the liver, lymph, etc., will be removed from the body by way of the major eliminative pathways - like the bowells and kidney. However, when operating properly READ: in good health, the skin is itself a major eliminative organ, so it seems reasonable to expect that  - depending on all the variables in play, especially those that manifest differently from one person (and their conditions) to the next,  there is a chance that some of the toxins drawn out will come all the way out to the surface of the skin and be absorbed by the cotton/flannel pack. 

To quickly recap the procedure, use a piece of natural material, like white flannel, large enough to cover the area of the body that will have the Castor oil fomentation applied to it; anywhere from a piece big enough to cover the area of the liver, all the way up to covering the entire upper torso from neck to groin. Soak the material with Castor Oil, then squeeze the material enough to wring it out eought so that it is not a sopping wet, dripping mess. Apply the oiled material flat onto the area of the body to be treated. Place either a damp towell OR piece of plastic over top of the oil-soaked material. * see more below. Then place a source of warm heat over top of the material that is covering the oiled material. IE> the oiled material is in direct contact with the skin, some other material is placed over top this material, see below for options. Regardless of how large an area being treated, the heat source is to be applied only in the area of the liver. The heat source is what helps to stimulte the fomenation effect. Leave all this in place, to foment, for 90 minutes. It is best to be lying down in bed during this time. At the end of 90 minutes, remove the heat, remove the material covering the oiled flannel (to be clearned/laundered before next use), and  remove the oiled flannel and place it into an airtight container in a cool dark place until it is needed for use the next time (do not attempt to clean/launder the oiled flannel, just put it away in an air-tight container.  Now might be a good time to take a bath or shower to clean the area of the body that was treated with the fomenation. Cayce suggests that a little baking powder can be used to help clean.

Variations, additions, subtractions and options: 

Some people advise the use of plastic wrap as the material to use for placing as a cover directly over top the oiled  flannel. Doc John himself often advises the use of plastic wrap to help hold in the moisture of various fomentations, but, for whatever reason, his instructions for Castor Oil fomenation do not mention the use of plastic wrap. Instead, he advised the use of a damp towell. If one uses a towell, use one made of natural material like cotton / flannel, wool, or silk. The towell needs to be damp, not sopping dripping wet. The dampness, along with the heat, helps stimulate the fomentation effect. So, don't use a sopping wet towell, use one that has been thoroughly soaked but then wrung out enough that it is still plenty damp but not dripping wet.  The idea is to not let the oil pack dry but insted to keep it surrounded with moist air/heat for the duration..... this is what a fomenation is.... a moist warm covered-up environment wherein things begin to "happen". The use of plastic will definitely help to keep the fomenation moist, but there is some concern that depending on which grade of plastic is used, the plastic may (potentially) be of a grade that imparts undesirable components. There are no doubt all kinds of pros and cons on this that may lead to it's own heted debate. You make the call. 

As for heat source, there are three basic choices: hot water bottle; a naturally made heat bag; an electric heating pad. The hot water bottle will likely require being re-warmed several times during the course of 90 minutes and this will be an inconvenience especially for people who live alone. The electric heating pad solves this problem but also introduces the potential for electric shock. Even by today's standards IE> the efforts of the institution of UL notwithstanding, this remains a situation that people must treat with some care. The natural heat bag can be home-made. This was picked up from Dr. Mom (Sandra Ellis). She describes how to make these out of regular, dried, field corn that is then used as filling material inside a little bag....pillow, that one must sew together using some simple, natural material, like cotton, wool, flanel or silk. Have an old flannel shirt you're are thinking about discarding?  If you are in a creative mode, you could cut it up into appropriate sections and then make into a home-made heat bag.  Once such a bag is made and heated, this bag will retain the heat for at least as long (if not longer) as a hot water bottle. The question then becomes - how does one heat their home-made bag? Two basic choices: microwave, conventional oven. Either route will require some experiementation in order to figure out what temperature setting the oven must be set at, and for how long, in order to heat this home-made bag to an acceptable temperature rather than nuking or baking it to a crisp (or starting a fire in your oven). This is also a good time to point out that that one should not heat their heat bag/bottle/pad to the extent that it will cause skin burns when placed atop the fomenation. Warm heat is sufficient in this instance, it does not need to be hot heat.

Doc John advises this Castor Oil Fomentation should be done 3 days in a row, followed by 3 days of spending 5 to 10 minutes massaging olive oil - in circular motions towareds/around the heart, into the same area of the body that was treated with the fomenation. This will help the healing/correcting process. The 7th day is reserved for rest. Then this cycle is repeated starting on the 8th day - 3 days of fomentating, 3 days of olive oil massaging, and a day of rest. This cycle of 6 days on, one day off, is repeated for as long as is required  - a week, a month, a half year, whatever it takes in order for the person to clear the condition they are treating.