Hi - further to Calgal's response, I have placed many postings on Medhelp and probably the most relevant one for your question can be found by logging on to:-
Please have a look at that and do come back with any further questions.
In my experience you do not have to make great changes to your diet after the surgery. However the frequency of your motions will increase as will their composition (i.e. they will become quite "loose and watery". I found that a high fibre diet helped and especially eating home made muesli (oats, bran, grated fruit, lemon juice all soaked in milk etc). I liken this to a liquid spillage on the kitchen floor on which you throw sawdust to make the spillage more solid and easier to scoop up. Same analogy!!
Scarring will be lessened if the surgery can be performed laparoscopically. My surgery was fully "invasive" and there was a 10-11 inch scar which has faded over the years.