Any advice on how to prepare my body for treatmen

Treatment can affect everyone differently, but there are some side effects that are quite common for which you can be prepared.  I weighed 105 pounds at the time of diagnosis and, due to the fact that the treatment killed my appetite towards the end, I lost about 13 pounds, weighing in at a hefty (not!) 92 pounds at one of my doctor's visits.  If you are already on the light side, weight-wise, be aware of this.  You might even want to gain a little weight ahead of time.  Diarrhea is a common side effect, so having items on hand to combat that are good--Imodium, for sure.  The BRAT diet (bananas, rice--white, applesause, and toast--white) are foods that can be eaten that MAY help with diarrhea.  If your doctors haven't already given you prescriptions for pain and nausea, ask them.  Nausea meds are most effective when taken at the earliest onset of queasiness.  Be aware that mouth sores and mouth tenderness are quite common during this treatment.  Swishing regularly with a mixture of water and baking soda or salt can help ward off mouth sores.  Try to have some good high protein foods on hand, such as eggs, fish and chicken.  Protein helps to promote healing.  If you notice your appetite tanking, get foods that you like and have a taste for.  However, be aware that sometimes what sounds good right now to you might be offputting 5 minutes from now.  That happened to me quite often.  My insides could not handle fruits and veggies very well during that time (and still can't sometimes!).  Yogurt is good for the insides, so you might want to have some on hand.  Keep in mind that your anal area may get very tender and sore, which often presents a problem with keeping things clean there, particularly if diarrhea is an issue.  Baby wipes may be good to try, but most, if not all, are NOT flushable.  Some people buy bidet attachments for their toilets.  I did not, so I really don't have a lot of information about those.  You will likely have some fatigue, so prepare to rest when your body tells you to do so.  I drove myself to treatment most days, but must admit, towards the end it was rough.  So, having someone lined up to drive you, should you just wish to have someone take you or should you get to a point where you are no longer up for driving, would be advisable.  Loose clothing will be best, so make sure you have some items that will not rub against your skin anymore than possible.  Avoiding germs when in public is important, as your defenses against such bugs as colds, etc., will be down.  Wash hands often and try to avoid places that might be particularly germy, if at all possible.  Some people even wear masks when out in public places to avoid picking up germs.  

If I think of anything else, I will add it.  I'm sure others will chime in with other suggestions as well.  I wish you all the very best as you near the beginning of treatment.  You will get through this, you will! 

You may want to ask the radiation oncologist or his/her nurse about vaginal dilators.  Vaginal stenosis is a possible side effect of radiation.   Vaginal dilators are often recommended shortly after the end of treatment .  Some people have started using them before treatment begins and even during treatment if possible and not too painful.

I also drank Ensure.  I started one chocolate ensure a day prior to treatment and continued throughout.  I was about 103 lbs. going into treatment

due to being so sick for so long and not being diagnosed correctly.  I had 2 rounds of chemo and 6 weeks daily radiation.   I found putting a couple ice cubes

in it and drinking it out of a nice glass, like a wine glass, helped!  Best wishes to you.  Redhawkgirl