Until you consider yourself an old pro at doing colonics and know how your body reacts, I would recommend that you at least refrain from eating for a few hours before the colonic.
For even better results, the day before your appointment have two salads, one with your lunch and one with your dinner. One thing you could do that would be helpful, but not necessary would be to add at least one tablespoon (or more)of cooked corn. ( It is one thing that is very identifiable, so when we see corn, we will then have an idea of how far in the colon we are)

Do not eat any red meat, rice, pasta, bread or anything you consider to be difficult to digest, the day before or on the day of your colonic. Do not eat two hours before your appointment. While it is important to have a hydrated body, do not drink a lot right before your appointment. You don’t want to have to go to the restroom in the middle of the procedure. In general, once you have to get off the table, the session is ended.

Some people coordinate their colonics with some type of a major cleanse approximately every 6 mo.     This can be anything from complete fasting, juice fasting or an actual cleansing program. This is up to each individual or the health care professional for the individual. Some people do colonics not necessarily for the cleansing effect but because they are constipated, maybe from insufficient water, bad diet, a medication or lazy colon. (we consider constipation to be: *having a bowel movement less often than once a day. *extremely hard lumps. *anything that looks extremely dry. *needing to push and strain to have the bowel movement. *Anything that seems painful or feels like the anus might tear.

Some people,especially if they are feeling constipated, like to have a cup of laxative type tea (such as "Smooth Move” ) the night before . Be careful with this one if you have never used it before, they can affect everyone differently. Never have more than one cup if you have never used it before. They can cause discomfort, cramps, or diarrhea depending on the brand and your system.

Some people do nothing to prepare for their colonic. Especially if they are on a maintenance schedule. If you are cleansing the colon on a regular basis then there is less chance that old hard stuff is stuck to the sides of the colon.

People having the following are required to have a doctor’s note:
Abdominal hernia
Abdominal surgery
Abdominal Tumors
Acute Liver Failure
Aneurysm
Carcinoma
Cardiac Conditions
Chrohns Disease
Ulcerative Colitis
Dialysis patients
Diverticulitis
Fissures or Fistulas
Hemorrhaging
Hemorrhoidectomy
Intestinal Perforation
Lupus
Pregnancy
Rectal Surgery
Renal Insufficiencies