As has been said above, warm water is your best friend when having a wee, it also helps clean it afterwards which is a bonus and alot of baths in plain water, gently stroke where the stitches are when you are in the bath to clean the area. x
My mum said when doing loo use a squirty bottle of warm water and spray down there while doing it. Also a ice pack helps when ur not doing anything just keep it against ur bits xx